Registration of Securities issued in Business Combination Transaction (Form S-4)

As filed with the Securities and Exchange Commission on March 20, 2026

No. 333-     

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

IonQ, Inc.

(Exact name of registrant as specified in its charter)

4505 Campus Drive, College Park, MD 20740

(301) 298-7997

(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Paul T. Dacier

Chief Legal Officer and Corporate Secretary

IonQ, Inc.

4505 Campus Drive, College Park,

MD 20740

(301) 298-7997

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies of all communications, including communications sent to agent for service, should be sent to:

Approximate date of commencement of proposed sale to the public: As soon as practicable after this Registration Statement becomes effective and all other conditions to the proposed Mergers described in the enclosed proxy statement/prospectus have been satisfied or waived.

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box. ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act:

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer) ☐

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

and vote on such stockholder's behalf. Such proxy need not be a holder of SkyWater common stock. We urge you to read this proxy statement/prospectus and the annexes and documents incorporated by reference carefully. You should also carefully consider the risks that are described in the "Risk Factors" section beginning on page 26.

The SkyWater Board has unanimously determined that the Merger Agreement and the transactions contemplated thereby, including the Mergers, are fair to and in the best interests of the SkyWater stockholders, approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Mergers, and directed that the Merger Agreement be submitted to the SkyWater stockholders for adoption at a meeting of such stockholders, and unanimously recommends that SkyWater stockholders vote "FOR" the proposal to approve and adopt the Merger Agreement and the transactions contemplated thereby, including the Mergers.

Your vote is very important regardless of the number of shares of SkyWater common stock that you own.

Whether or not you plan to attend the special meeting, please submit your proxy as soon as possible by following the instructions on the accompanying proxy card to make sure that your shares are represented at the meeting. If your shares are held in the name of a broker, bank or other nominee, please follow the instructions on the voting instruction form furnished by the broker, bank or other nominee. You must provide voting instructions by filling out the voting instruction form in order for your shares to be voted.

The special meeting will be held in a virtual meeting format only. You will not be able to attend the special meeting physically in person.

Thank you for your continued support, interest and investment in SkyWater.

Very truly yours,

Timothy E. Baxter

Chairman of the Board of Directors

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the Mergers or the other transactions described in this proxy statement/prospectus or the securities to be issued in connection with the Mergers or determined if this proxy statement/prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

This proxy statement/prospectus is dated [ ], 2026, and is first being mailed to stockholders of SkyWater on or about [ ], 2026.

2401 East 86th Street

Bloomington, Minnesota 55425

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NOTICE OF SPECIAL MEETING OF STOCKHOLDERS

To be held on [ ], 2026

To the Stockholders of SkyWater Technology, Inc.:

We are pleased to invite you to attend the special meeting of stockholders of SkyWater Technology, Inc., a Delaware corporation ("SkyWater"), which will be held at [ ]:[ ] [a.m./p.m.], Central Time, on [ ], 2026, virtually at www.virtualshareholdermeeting.com/SKYT2026SM, for the following purposes:

SkyWater will transact no other business at the special meeting except such business as may properly be brought before the special meeting or any adjournment or postponement thereof by or at the direction of the SkyWater board of directors (the "Skywater Board"). Please refer to the proxy statement/prospectus of which this notice is a part for further information with respect to the business to be transacted at the special meeting.

The special meeting will be held in a virtual meeting format only. You will not be able to attend the special meeting physically in person.

SkyWater fixed the close of business on [ ], 2026, as the record date for the special meeting. Only SkyWater stockholders of record at the record date are entitled to receive notice of, and to vote at, the special meeting or any adjournment or postponement thereof. A complete list of stockholders entitled to vote at the special meeting will be available for inspection for a period of 10 days ending the day prior to the special meeting and during the special meeting at www.virtualshareholdermeeting.com/SKYT2026SM by entering the control number provided on your proxy card, voting instruction form or notice.

Completion of the Mergers is conditioned on adoption of the Merger Agreement by the SkyWater stockholders, which requires the affirmative vote of holders of a majority of the outstanding shares of SkyWater common stock entitled to vote thereon.

The SkyWater Board has unanimously determined that the Merger Agreement and the transactions contemplated thereby, including the mergers described therein (the "Mergers"), are fair to and in the best interests of the SkyWater stockholders, approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Mergers, and directed that the Merger Agreement be submitted to the SkyWater stockholders for adoption at a meeting of such stockholders and unanimously recommends that SkyWater stockholders vote "FOR" the Merger Agreement proposal and "FOR" the adjournment proposal.

Your vote is very important regardless of the number of shares of SkyWater common stock that you own. If you plan to attend the special meeting virtually, please follow the instructions as outlined in this proxy statement/prospectus. Whether or not you expect to attend the special meeting virtually, we urge you to submit your vote in advance of the meeting. If your shares are held in the name of a broker, bank or other nominee, please vote by following the instructions on the voting instruction form furnished by the broker, bank or other nominee. If you hold your shares in your own name, submit a proxy to vote your

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shares as promptly as possible by (i) visiting the internet site listed on the accompanying proxy card, (ii) calling the toll-free number listed on the proxy card or (iii) submitting your proxy card by mail by using the self-addressed, stamped envelope provided. Submitting a proxy will not prevent you from voting virtually at the meeting, but it will help to secure a quorum and avoid added solicitation costs. Any eligible holder of SkyWater common stock may vote virtually at the special meeting, thereby revoking any previous proxy. In addition, a proxy may also be revoked in writing before the special meeting in the manner described in the proxy statement/prospectus of which this notice is a part.

The proxy statement/prospectus of which this notice is a part provides a detailed description of the Mergers and the Merger Agreement and the other matters to be considered at the special meeting. We urge you to carefully read this proxy statement/prospectus, including any documents incorporated by reference herein, and the annexes in their entirety. In particular, we urge you to carefully read the section titled "Risk Factors" beginning on page [ ].

If you have any questions concerning the Mergers or this proxy statement/prospectus, would like additional copies or need help voting your shares of SkyWater common stock, please contact SkyWater's proxy solicitor:

Innisfree M&A Incorporated

Shareholders, please call toll-free: +1 (888) 750-5835 (U.S. and Canada)

              +1 (412) 232-3651 (all other countries)

Banks and brokerage firms may call: +1 (212) 750-5833 (collect)

By Order of the SkyWater Board of Directors,

Christopher Hilberg

Secretary

[ ], 2026

Bloomington, Minnesota

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REFERENCES TO ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates by reference important business and financial information about IonQ, Inc. ("IonQ") and SkyWater Technology, Inc. ("SkyWater") from other documents that are not included in or delivered with this proxy statement/prospectus. For a listing of the documents incorporated by reference into this proxy statement/prospectus, see "Where You Can Find More Information" beginning on page [ ].

You can obtain any of the documents incorporated by reference into this proxy statement/prospectus without charge by requesting them in writing or by telephone as follows:

For information related to SkyWater:

SkyWater Technology, Inc.

Attention: Secretary

2401 East 86th Street

Bloomington, MN 55425

Telephone: (952) 851-5200

For information related to IonQ:

IonQ, Inc.

Attention: Investor Relations

4505 Campus Drive

College Park, MD 20740

Telephone: (301) 298-7997

To receive timely delivery of the documents in advance of the special meeting of SkyWater stockholders, you should make your request no later than [ ], 2026, which is five business days before the meeting.

You may also obtain any of the documents incorporated by reference into this proxy statement/prospectus without charge through the Securities and Exchange Commission (the "SEC") website at www.sec.gov. In addition, you may obtain copies of documents filed by IonQ with the SEC by accessing investors.IonQ.com under the tab "Financials" and then under the heading "SEC Filings." You may also obtain copies of documents filed by SkyWater with the SEC by accessing ir.skywatertechnology.com under the tab "Financials" and then under the heading "SEC Filings."

We are not incorporating the contents of the websites of the SEC, IonQ, SkyWater or any other entity into this proxy statement/prospectus. We are providing information about how you can obtain certain documents that are incorporated by reference into this proxy statement/prospectus at these websites only for your convenience.

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ABOUT THIS PROXY STATEMENT/PROSPECTUS

This document, which forms part of a registration statement on Form S-4 filed with the SEC by IonQ (File No. 333-[ ]), constitutes a prospectus of IonQ under Section 5 of the Securities Act of 1933, as amended (the "Securities Act"), with respect to the IonQ common stock to be issued to SkyWater stockholders pursuant to the Merger Agreement. This document also constitutes a proxy statement of SkyWater under Section 14(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). It also constitutes a notice of meeting with respect to the special meeting, at which SkyWater stockholders will be asked to consider and vote on the adoption of the Merger Agreement and any other related proposals.

IonQ has supplied all information contained in, and incorporated by reference into, this proxy statement/prospectus relating to IonQ, Merger Subsidiary 1 and Merger Subsidiary 2, and SkyWater has supplied all such information relating to SkyWater.

You should rely only on the information contained in, and incorporated by reference into, this proxy statement/prospectus. IonQ and SkyWater have not authorized anyone to provide you with information other than the information that is contained in, or incorporated by reference into, this proxy statement/prospectus. IonQ and SkyWater take no responsibility for, and can provide no assurances as to the reliability of, any other information that others may give you. This proxy statement/prospectus is dated [ ], 2026, and you should not assume that the information contained in this proxy statement/prospectus is accurate as of any date other than such date. Further, you should not assume that the information incorporated by reference into this proxy statement/prospectus is accurate as of any date other than the date of the incorporated document. Neither the mailing of this proxy statement/prospectus to SkyWater stockholders nor the issuance by IonQ of shares of IonQ common stock pursuant to the Merger Agreement will create any implication to the contrary.

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TABLE OF CONTENTS

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ANNEXES

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QUESTIONS AND ANSWERS ABOUT THE MERGERS AND THE SPECIAL MEETING

The following questions and answers briefly address some commonly asked questions about the Mergers and the special meeting of SkyWater stockholders (the "special meeting"). They may not include all of the information that is important to stockholders of SkyWater. SkyWater stockholders should carefully read this entire proxy statement/prospectus, including the annexes and the other documents referred to or incorporated by reference in this proxy statement/prospectus. See "Where You Can Find More Information" beginning on page [ ] of this proxy statement/prospectus.

Q: What is the Merger Agreement and what are the Mergers?

IonQ, Inc. ("IonQ"), Iris Merger Subsidiary 1 Inc. ("Merger Subsidiary 1"), Iris Merger Subsidiary 2 LLC ("Merger Subsidiary 2," and collectively with Merger Subsidiary 1, the "Merger Subsidiaries"), and SkyWater Technology, Inc. ("SkyWater") have entered into an Agreement and Plan of Merger, dated as of January 25, 2026 (as it may be amended from time to time, the "Merger Agreement"). Merger Subsidiary 1 and Merger Subsidiary 2 are both direct, wholly-owned subsidiaries of IonQ. A copy of the Merger Agreement is attached as Annex A to this proxy statement/prospectus. The Merger Agreement contains the terms and conditions of the proposed acquisition of SkyWater by IonQ. Under the Merger Agreement, subject to satisfaction (or, to the extent permitted by law and in accordance with the Merger Agreement, waiver) of the conditions to the Mergers set forth in the Merger Agreement and described in this proxy statement/prospectus, (i) Merger Subsidiary 1 will merge with and into SkyWater in accordance with the General Corporation Law of the State of Delaware ("DGCL") (the "First Merger"), with SkyWater continuing as the surviving corporation in the First Merger (the "First Surviving Corporation"), and (ii) immediately following the effective time of the First Merger (which is the "Effective Time"), and as part of the same plan, the First Surviving Corporation will merge with and into Merger Subsidiary 2 in accordance with the Delaware General Corporation Law and the Delaware Limited Liability Company Act (the "Second Merger"), with Merger Subsidiary 2 surviving as the surviving company (the "Surviving Company"). Following the Second Merger, the Surviving Company will be a wholly-owned direct subsidiary of IonQ (the Second Merger together with the First Merger, the "Mergers" or the "Transactions").

As a result of the Mergers, SkyWater will become a direct, wholly-owned subsidiary of IonQ and will no longer be a publicly held company. Following the Mergers, SkyWater common stock will be delisted from the Nasdaq Capital Market ("Nasdaq") and will be deregistered under the Exchange Act, after which SkyWater will no longer be required under SEC rules and regulations to file periodic reports with the SEC in respect of SkyWater common stock.

Q: Why am I receiving this proxy statement/prospectus?

IonQ and SkyWater are sending these materials to SkyWater stockholders to help them decide how to vote their shares of SkyWater common stock with respect to the Mergers and other matters to be considered at the special meeting.

The Mergers cannot be completed unless SkyWater stockholders adopt the Merger Agreement with the affirmative vote of the holders of a majority of the outstanding shares of SkyWater common stock entitled to vote thereon. SkyWater is holding a special meeting of its stockholders to vote on the proposal to adopt the Merger Agreement and other related proposals. Information about this special meeting, the Mergers and the other business to be considered by stockholders at the special meeting is contained in this proxy statement/prospectus.

This proxy statement/prospectus constitutes both a proxy statement of SkyWater and a prospectus of IonQ. It is a proxy statement because the board of directors of SkyWater (the "SkyWater Board") is soliciting proxies from its stockholders. It is a prospectus because IonQ will issue shares of its common stock in exchange for outstanding shares of SkyWater common stock in the Mergers.

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Q: What will SkyWater stockholders receive in the Mergers?

In the Mergers, SkyWater stockholders will receive (i) an amount of cash equal to $15.00, without interest (the "Per Share Cash Consideration"), and (ii) such number of validly issued, fully paid and non-assessable shares of the common stock of IonQ, par value $0.0001 per share, equal to the Exchange Ratio (the "Per Share Stock Consideration" and together with the Per Share Cash Consideration, the "Merger Consideration"), plus cash in lieu of any fractional shares to which such share of SkyWater common stock would otherwise be entitled. The "Exchange Ratio" means the following (in each case rounded to four decimals): (A) if the IonQ Trading Price is an amount equal to or less than $37.99, then the Exchange Ratio shall be 0.5265; (B) if the IonQ Trading Price is an amount greater than $37.99 but less than $60.13, then the Exchange Ratio shall be equal to the quotient obtained by dividing $20 by the IonQ Trading Price; and (C) if the IonQ Trading Price is an amount greater than or equal to $60.13, then the Exchange Ratio shall be 0.3326. The "IonQ Trading Price" is the volume-weighted average price (VWAP), rounded to four decimal places, of IonQ common stock on all exchanges as reported by Bloomberg L.P. on the VWAP function for the ticker "[IonQ, Inc. US Equity]" for the 20 full consecutive trading days prior to, but not including, the third business day prior to the Closing Date, calculated from market open (9:30 AM ET) on the first day of the measurement period to market close on the last day of the measurement period (4:00 PM ET).

No fractional shares of IonQ common stock will be issued in connection with the Mergers. Each holder of SkyWater common stock that otherwise would have been entitled to receive a fractional share of IonQ common stock will instead have the right to receive an amount in cash, without interest, rounded to the nearest cent, in lieu of such fractional share. The value of such cash payment will be calculated by the exchange agent and will represent the holder's proportionate interest in a trust of proceeds established from the open-market sale of that number of shares of IonQ common stock equal to the excess of (x) the aggregate number of shares of IonQ common stock to be delivered to the exchange agent by IonQ pursuant to the terms of the Merger Agreement over (y) the aggregate number of whole shares of IonQ common stock to be distributed to the holders of certificates or book-entry shares previously representing any such shares of SkyWater common stock pursuant to the Merger Agreement. Because the Per Share Stock Consideration will be a fixed amount to the extent the IonQ Trading Price is an amount equal to or less than $37.99 or greater than or equal to $60.13, the implied value of the Merger Consideration will fluctuate with the market price of IonQ common stock until the Transactions are complete and the market price of the shares of IonQ common stock that SkyWater stockholders will receive upon completion of the Mergers could be greater than, less than or the same as the market price of IonQ common stock on the date of this proxy statement/prospectus or on the date of the SkyWater special meeting.

For more details on the Merger Consideration, see "The Merger Agreement-Merger Consideration" beginning on page [ ].

Q: What equity stake will SkyWater stockholders hold in IonQ immediately following the Mergers?

If the IonQ Trading Price were equal to the closing price of IonQ common stock on the New York Stock Exchange (the "NYSE") on [ ], 2026, the last trading day before the date of this proxy statement/prospectus, the Exchange Ratio would be [ ]. At this Exchange Ratio, it is estimated that, immediately after completion of the Mergers, IonQ stockholders as of immediately prior to the Mergers would hold approximately [ ]% and SkyWater stockholders as of immediately prior to the Mergers (disregarding any shares of IonQ common stock held by SkyWater stockholders immediately prior to the Mergers) would hold approximately [ ]% of the outstanding shares of IonQ common stock, each on a fully diluted basis. The exact equity stake of former SkyWater stockholders in IonQ immediately following the completion of the Mergers will depend on (i) the number of outstanding shares of common stock and outstanding stock-based awards of IonQ and SkyWater immediately prior to the Effective Time and (ii) the final Exchange Ratio.

For more details on the Merger Consideration and the treatment of SkyWater stock-based awards, see "The Merger Agreement-Merger Consideration" beginning on page [ ] and "The Merger Agreement-Merger Consideration-Treatment of SkyWater Equity Awards" beginning on page [ ], respectively.

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Q: Are the Mergers subject to conditions?

The respective obligations of IonQ and SkyWater to complete the Mergers are subject to the satisfaction or waiver of a number of conditions, including (i) the Merger Agreement having been adopted by SkyWater stockholders, (ii) any waiting period applicable to the Mergers under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act"), having expired or having been terminated, (iii) the absence of any applicable law or regulation enacted or deemed applicable to the Mergers by a governmental authority that makes consummation of the Mergers illegal and any judgment, injunction, order or decree prohibiting or enjoining the consummation of the Mergers, (iv) the approval for listing on the NYSE of the IonQ common stock to be issued in connection with the Mergers and (v) the registration statement on Form S-4, of which this proxy statement/prospectus forms a part, becoming effective under the Securities Act and not being the subject of any stop order or any proceedings by the SEC seeking a stop order. The completion of the Mergers is not subject to the approval of IonQ stockholders or the receipt of financing by IonQ.

See "The Merger Agreement-Conditions to Completion of the Mergers" beginning on page [ ].

Q: When do SkyWater and IonQ expect to complete the Mergers?

IonQ and SkyWater currently expect the Mergers to be completed in the second or third quarter of 2026, subject to the expiration or termination of the waiting period (and any extensions thereof) applicable to the Mergers under the HSR Act and the satisfaction or waiver of the other closing conditions contained in the Merger Agreement. However, neither IonQ nor SkyWater can predict the actual date on which the Mergers will be completed because it is subject to conditions beyond each company's control, and it is possible that such conditions could result in the Mergers being completed earlier or later than expected or not being completed at all. The Merger Agreement may be terminated by either party if the Mergers have not been completed by January 25, 2027 (the "End Date"), subject to two automatic 90-day extensions if the sole unsatisfied closing conditions at such time relate to regulatory approvals. For additional details regarding when the Mergers are expected to be completed, see "The Merger Agreement-Conditions to Completion of the Mergers" beginning on page [ ] and "The Merger Agreement-Termination Fees" beginning on page [ ].

Q: What happens if the Mergers are not completed?

If the Merger Agreement is not adopted by SkyWater stockholders or if the Mergers are not completed for any other reason, SkyWater stockholders will not receive any consideration for their shares of SkyWater common stock. Instead, SkyWater will remain an independent public company, SkyWater common stock will continue to be listed and traded on Nasdaq and registered under the Exchange Act and SkyWater will continue to file periodic reports with the SEC. Under specific circumstances, SkyWater may be required to pay IonQ a termination fee of $51,573,958.07 (the "Termination Fee"). Under specific circumstances, SkyWater may be required to issue to IonQ and IonQ will purchase from SkyWater, an aggregate of 2,857,143 shares of newly issued SkyWater common stock for $100,000,000. See "The Merger Agreement-Termination of the Merger Agreement" beginning on page [ ].

Q: Will the IonQ common stock I acquire in the Mergers receive a dividend?

After the closing of the Mergers, as a holder of IonQ common stock, you will receive the same dividends on shares of IonQ common stock that all other holders of shares of IonQ common stock will receive with any dividend record date that occurs after the closing of the Mergers.

Q: What are SkyWater stockholders being asked to vote on, and why is this approval necessary?

SkyWater stockholders are being asked to vote on the following proposals:

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Approval of the Merger Agreement proposal by the affirmative vote of holders of a majority of the outstanding shares of SkyWater common stock entitled to vote thereon is required for completion of the Mergers. The completion of the Mergers is not conditioned on the adjournment proposal.

Q: What vote is required to approve each proposal at the special meeting?

The Merger Agreement proposal: The affirmative vote of holders of a majority of the outstanding shares of SkyWater common stock entitled to vote thereon is required to approve the Merger Agreement proposal (the "SkyWater Stockholder Approval"). Certain stockholders of SkyWater, who collectively held approximately 19.87% of the outstanding shares of SkyWater common stock as of January 25, 2026, have entered into voting agreements pursuant to which they have agreed to vote their shares in favor of the Merger Agreement proposal. See "The Voting Agreement" beginning on page [ ].

The adjournment proposal: The affirmative vote of the holders of a majority of the outstanding shares of SkyWater common stock, present in person or represented by proxy at the special meeting and entitled to vote thereon, is required to approve the adjournment proposal. If SkyWater stockholders approve the adjournment proposal, subject to the terms of the Merger Agreement, SkyWater could adjourn the special meeting and use the additional time to solicit additional proxies, including soliciting proxies from SkyWater stockholders who have previously voted. SkyWater does not intend to call a vote on the adjournment proposal if the Merger Agreement proposal is approved at the special meeting.

Q: What constitutes a quorum?

The presence at the special meeting, in person or by proxy, of the holders of a majority of the outstanding shares of SkyWater common stock entitled to vote at the special meeting will constitute a quorum for the transaction of business at the special meeting. Virtual attendance at the special meeting will constitute presence in person for the purpose of determining the presence of a quorum for the transaction of business at the special meeting. Abstentions will count as votes present and entitled to vote for the purpose of determining the presence of a quorum for the transaction of business at the special meeting. Brokers, banks or other nominees that hold shares for beneficial owners do not have discretionary authority to vote the shares as to any matter at the meeting without receiving voting instructions from the beneficial owners. Such shares will be considered to be broker non-votes and will not be counted as present for quorum purposes.

A quorum is necessary to transact business at the special meeting. The bylaws of SkyWater ("SkyWater's Bylaws") provide that if a quorum fails to attend any meeting, the chair of the meeting or a majority of the stockholders who are present in person or by proxy and entitled to vote at the special meeting may adjourn the meeting from time to time, without notice other than by announcement at the meeting, to another date, place, if any, and time until a quorum is present. If the adjournment is for more than 30 days or if after the adjournment, a new record date is fixed for the adjourned meeting, SkyWater will provide a notice of the adjourned meeting to each stockholder of record entitled to vote at the meeting.

Q: How does the SkyWater Board recommend that I vote?

The SkyWater Board unanimously recommends that SkyWater stockholders vote "FOR" the Merger Agreement proposal and "FOR" the adjournment proposal.

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Q: What do I need to do now?

After carefully reading and considering the information contained in, and incorporated by reference into, this proxy statement/prospectus, please vote your shares as soon as possible so that your shares will be represented at the special meeting. Please follow the instructions set forth on the accompanying proxy card or on the voting instruction form provided by the record holder if your shares are held in the name of your broker, bank or other nominee.

Please do not submit your SkyWater stock certificates at this time. If the Mergers are completed, you will receive instructions for surrendering your SkyWater stock certificates in exchange for shares of IonQ common stock from the exchange agent.

Please carefully consider the information contained in, and incorporated by reference into, this proxy statement/prospectus. Whether or not you plan to attend the special meeting, SkyWater encourages you to submit your proxy to vote via the internet, by telephone or by mail so that your shares will be voted in accordance with your wishes even if you later decide not to attend the special meeting.

Q: How can I attend the special meeting?

Stockholders as of the close of business on [ ], 2026 (the "record date"), may attend, vote and submit questions virtually at the special meeting by logging in at www.virtualshareholdermeeting.com/SKYT2026SM. To log in, stockholders (or their authorized representatives) will need the control number provided on their proxy card or voting instruction form.

Q: How do I vote?

If you are a stockholder of record of SkyWater as of the close of business on the record date, you may submit your proxy before the special meeting in one of the following ways:

If you are a stockholder of record, you may also cast your vote virtually at the special meeting by following the instructions at www.virtualshareholdermeeting.com/SKYT2026SM. If you decide to attend the special meeting virtually and vote at the meeting, your vote will revoke any proxy previously submitted.

If your shares are held in "street name" through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your shares. If your shares are held in "street name" and you intend to vote at the special meeting, you may cast your vote virtually at the special meeting by following the instructions at www.virtualshareholdermeeting.com/SKYT2026SM. Your vote at the special meeting will revoke any proxy previously submitted on your behalf by your broker, bank or other nominee.

The meeting will begin promptly at [  ]:[  ] [a.m./p.m.], Central Time, on [    ], 2026. SkyWater encourages its stockholders to access the meeting prior to the start time leaving ample time for check-in. Please follow the instructions as outlined in this proxy statement/prospectus.

Even if you plan to attend the special meeting, SkyWater recommends that you vote your shares in advance as described below so that your vote will be counted even if you later decide not to or become unable to attend the special meeting.

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Q: When and where is the special meeting of stockholders? What must I bring to attend the special meeting?

The special meeting of SkyWater stockholders will be held virtually at www.virtualshareholdermeeting.com/SKYT2026SM, at [  ]:[  ] [a.m./p.m.], Central Time, on [    ], 2026. Online access will begin at [  ]:[  ] [a.m./p.m.], Central Time, and SkyWater encourages its stockholders to access the meeting prior to the start time. Even if you plan to attend the special meeting, SkyWater recommends that you vote your shares in advance as described above so that your vote will be counted if you later decide not to or become unable to attend the special meeting.

Q: What is the difference between holding shares as a stockholder of record and as a beneficial owner?

If your shares of SkyWater common stock are registered directly in your name with the transfer agent of SkyWater, Equiniti Trust Company, LLC, you are considered the stockholder of record with respect to those shares. As the stockholder of record, you have the right to vote or to grant a proxy for your vote directly to SkyWater or to a third party to vote at the special meeting.

If your shares are held by a broker, bank or other nominee, you are considered the beneficial owner of shares held in "street name," and your broker, bank or other nominee is considered the stockholder of record with respect to those shares. Your broker, bank or other nominee will send you, as the beneficial owner, voting instruction forms for you to use in directing the broker, bank or other nominee in how to vote your shares. You should follow the instructions provided by them to vote your shares. You are invited to attend the special meeting and you may cast your vote virtually at the special meeting by following the instructions at www.virtualshareholdermeeting.com/SKYT2026SM.

Q: If my shares are held in "street name" by a broker, bank or other nominee, will my broker, bank or other nominee vote my shares for me?

If your shares are held in "street name" in a stock brokerage account or by a broker, bank or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your broker, bank or other nominee. Please note that you may not vote shares held in street name by returning a proxy card or voting instruction form directly to SkyWater. Your broker, bank or other nominee is obligated to provide you with a voting instruction form for you to use. You may also cast your vote virtually at the special meeting by following the instructions at www.virtualshareholdermeeting.com/SKYT2026SM.

Applicable stock exchange rules permit brokers to vote their customers' stock held in street name on routine matters when the brokers have not received voting instructions from their customers. Those rules do not, however, allow brokers to vote their customers' stock held in street name on non-routine matters unless they have received voting instructions from their customers. In such cases, the uninstructed shares for which the broker is unable to vote are called broker non-votes. The Merger Agreement proposal and the adjournment proposal are non-routine matters on which brokers are not allowed to vote unless they have received voting instructions from their customers.

If you are a SkyWater "street name" stockholder and you do not instruct your broker, bank or other nominee on how to vote your shares:

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Q: What if I fail to vote or abstain?

For purposes of the special meeting, an abstention occurs when a stockholder attends the special meeting virtually and does not vote or returns a proxy with an "abstain" instruction.

Merger Agreement proposal: An abstention or failure to vote will have the same effect as a vote cast "AGAINST" the Merger Agreement proposal.

Adjournment proposal: An abstention will have the same effect as a vote cast "AGAINST" the adjournment proposal. If a SkyWater stockholder is not present virtually at the special meeting and does not respond by proxy, it will have no effect on the vote for the adjournment proposal (assuming a quorum is present).

Q: What will happen if I return my proxy card or voting instruction form without indicating how to vote?

If you sign and return your proxy card or voting instruction form without indicating how to vote on any particular proposal, the SkyWater common stock represented by your proxy will be voted as recommended by the SkyWater Board with respect to that proposal.

Q: May I change or revoke my vote after I have delivered my proxy card or voting instruction form?

Yes. If you are a record holder, you may change or revoke your vote before your proxy is voted at the special meeting as described herein. You may do this in one of four ways:

If you are a street name stockholder and you vote by proxy, you may later revoke your proxy by informing the holder of record in accordance with that entity's procedures.

Q: What are the material U.S. federal income tax consequences of the Mergers?

The U.S. federal income tax consequences of the Mergers will depend primarily upon whether the Mergers, taken together, qualify as a "reorganization" within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended (the "Code"). Assuming the Mergers so qualify, a U.S. Holder (as defined in "The Mergers-Material U.S. Federal Income Tax Consequences") will generally recognize a capital gain (but not loss) upon the exchange of SkyWater common stock for IonQ common stock up to the amount of cash consideration received pursuant to the Mergers (excluding any cash received in lieu of a fractional share of IonQ common stock, which shall be treated as discussed below under the section titled "Material U.S. Federal Income Tax Consequences-Tax Consequences if the Mergers Qualify for the Intended Tax Treatment- Receipt of cash in lieu of fractional shares" beginning on page [ ] of this proxy statement/prospectus).

However, SkyWater's obligation and IonQ's obligation to complete the Mergers are not conditioned on the Mergers being treated as a "reorganization" within the meaning of Section 368(a) of the Code or upon the receipt by IonQ or SkyWater of an opinion from counsel to that effect. IonQ and SkyWater have not sought, and will not seek, any ruling from the Internal Revenue Service (the "IRS") regarding any matters related to the Transactions, and as a result, there can be no assurance that the IRS would not assert that the Mergers do not qualify as a

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"reorganization" within the meaning of Section 368(a) of the Code, or that a court would not sustain such a position. Whether or not the Mergers will qualify as a reorganization may not be known until after the second to last trading day prior to the Closing Date.

If any requirement for qualification as a "reorganization" within the meaning of Section 368(a) of the Code is not met, then a U.S. Holder generally would recognize gain or loss in an amount equal to the difference, if any, between the fair market value of the IonQ common stock and the amount of cash consideration received in the Mergers, and such U.S. Holder's aggregate tax basis in the corresponding SkyWater common stock surrendered in the Mergers.

Neither SkyWater nor IonQ or any of their respective advisors or affiliates provides any assurances regarding the tax consequences of the Mergers, including whether the Mergers will qualify as a "reorganization" under Section 368(a) of the Code. All holders of SkyWater common stock should consult with their own tax advisor to determine the particular U.S. federal, state or local or non-U.S. income or other tax consequences of the Mergers to them. See "The Mergers-Material U.S. Federal Income Tax Consequences" beginning on page [ ] for additional information.

Q: Am I entitled to exercise appraisal rights in connection with the Mergers instead of receiving the Merger Consideration for my shares of SkyWater common stock?

Yes. SkyWater stockholders are entitled to appraisal rights in connection with the First Merger. To exercise such appraisal right, you must make a proper demand for appraisal of your shares of SkyWater common stock in accordance with Section 262 of the DGCL and otherwise comply with all applicable provisions of Section 262 of the DGCL. If this appraisal right is properly exercised, and assuming you do not fail to perfect, validly withdraw or otherwise lose your appraisal rights under Section 262 of the DGCL with respect to your shares of SkyWater common stock, your shares of SkyWater common stock will not be converted into or represent the right to receive the Merger Consideration, and you shall be entitled only to such rights as are granted by Section 262 of the DGCL to a holder of shares of SkyWater common stock that are outstanding immediately prior to the Effective Time (other than Cancelled Shares) and that are held by any person who is entitled to demand and properly demands appraisal of those shares pursuant to, and who complies in all respects with, Section 262 of the DGCL ("Appraisal Shares"). If any Appraisal Shares lose their status as such (through failure to perfect or otherwise), then such shares will thereupon be deemed, as of the Effective Time, to have been converted into, and shall represent only, the right to receive the Merger Consideration in accordance with the Merger Agreement, without interest thereon. The term "Cancelled Shares" means shares of SkyWater common stock owned by IonQ, Merger Subsidiary 1, Merger Subsidiary 2, SkyWater or any of their wholly-owned subsidiaries immediately prior to the Effective Time which are canceled at the Effective Time without any consideration being delivered in exchange therefor. For more information, see the section titled "Appraisal Rights " beginning on page [ ] of this proxy statement/prospectus.

Q: What is the source of the cash consideration for the Mergers?

IonQ expects to fund the aggregate Per Share Cash Consideration from cash on hand.

Q: What will happen to SkyWater stock-based awards?

SkyWater Stock Option Awards. At the Effective Time, each outstanding option to purchase shares of SkyWater common stock (each, a "SkyWater Option Award") that is outstanding, whether vested or unvested, will automatically be converted into an option to purchase a number of shares of IonQ common stock based on the Equity Award Exchange Ratio (as defined below) at an adjusted exercise price (as determined in accordance with the formula in the Merger Agreement), and otherwise will be subject to the same terms and conditions as applied immediately prior to the Effective Time. "Equity Award Exchange Ratio" means the sum of (i) the Exchange Ratio and (ii) the quotient, rounded to four decimal places, obtained by dividing (x) the Per Share Cash Consideration by (y) the IonQ Trading Price.

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SkyWater Employee RSU Awards. At the Effective Time, each award of restricted stock units relating to shares of SkyWater common stock held by a service provider other than a non-employee member of the SkyWater Board (each, a "SkyWater Employee RSU Award") that is outstanding, whether vested or unvested, will automatically be converted into a restricted stock unit award corresponding to a number of shares of IonQ common stock based on the Equity Award Exchange Ratio, and otherwise will be subject to the same terms and conditions (including any existing accelerated vesting provisions) as applied immediately prior to the Effective Time, with any related accrued but unpaid dividend equivalent rights carrying over and remaining payable in accordance with such preexisting terms.

SkyWater Director RSU Awards. Prior to the Effective Time, each award of restricted stock units relating to shares of SkyWater common stock held by a non-employee member of the SkyWater Board (each, a "SkyWater Director RSU Award") that is outstanding, whether vested or unvested, will automatically become fully vested and will be settled prior to the Effective Time, and any shares of SkyWater common stock issued thereunder will be treated in the same manner as all other shares of SkyWater common stock at the Effective Time.

Q: What will happen to the SkyWater Employee Stock Purchase Plan?

Following the date of the Merger Agreement, participation in SkyWater's 2021 Employee Stock Purchase Plan (the "ESPP") has been limited to employees who were participants as of January 25, 2026, and participants may not increase their payroll deduction elections or rate of contributions or make any separate non-payroll contributions. No new offering or purchase period will be commenced after the date of the Merger Agreement. Each participant's then-outstanding share purchase right under the ESPP will be exercised as of the earlier of the first scheduled purchase date following the date of the Merger Agreement or a date no later than the fifth trading day before the Effective Time. The ESPP will terminate as of the Effective Time. For more information, see "The Merger Agreement-Treatment of SkyWater Equity Awards" beginning on page [ ].

Q: What happens if I sell my shares of SkyWater common stock after the record date but before the special meeting?

The record date for the special meeting (the close of business on [ ], 2026) is earlier than the date of the special meeting and earlier than the date that the Mergers are expected to be completed. If you sell or otherwise transfer your shares of SkyWater common stock after the record date but before the date of the special meeting, you will retain your right to vote at the special meeting. However, you will not have the right to receive the Merger Consideration to be received by SkyWater stockholders in the Mergers. In order to receive the Merger Consideration, you must hold your shares through completion of the Mergers.

Q: Are there any risks that I should consider in deciding whether to vote in favor of the Mergers proposal?

Yes. You also should read and carefully consider the risk factors of IonQ and SkyWater contained in the documents that are incorporated by reference into this proxy statement/prospectus in the section titled "Risk Factors" beginning on page [ ].

Q: What should I do if I receive more than one set of voting materials?

If you hold shares of SkyWater common stock in "street name" and also directly as a record holder or otherwise or if you hold shares of SkyWater common stock in more than one brokerage account, you may receive more than one set of voting materials relating to the special meeting. Please complete, sign, date and return each proxy card (or cast your vote by telephone or internet as provided on your proxy card) or otherwise follow the voting instructions provided in this proxy statement/prospectus in order to ensure that all of your shares of SkyWater common stock are voted. If you hold your shares in "street name" through a broker, bank or other nominee, you should follow the procedures provided by your broker, bank or other nominee to vote your shares.

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Q: Who will tabulate and certify the vote?

Representatives of Broadridge Financial Solutions, Inc. ("Broadridge") will tabulate the votes cast at the special meeting and act as the Independent Inspector of Election.

Q: Where can I find the voting results of the special meeting?

The preliminary voting results will be announced at the special meeting. In addition, within four business days following certification of the final voting results, SkyWater intends to file the final voting results with the SEC on a Current Report on Form 8-K.

Q: Whom should I contact if I have any questions about the proxy materials or voting?

If you have any questions about the proxy materials, or if you need assistance submitting your proxy or voting your shares or need additional copies of this proxy statement/prospectus or the enclosed proxy card, you should contact the proxy solicitation agent for SkyWater, at:

Innisfree M&A Incorporated

Shareholders, please call toll-free: +1 (888) 750-5835 (U.S. and Canada)

               +1 (412) 232-3651 (all other countries)

Banks and brokerage firms may call: +1 (212) 750-5833 (collect)

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RISK FACTORS

In addition to the other information included in and incorporated by reference into this proxy statement/prospectus, including, among others, the matters addressed in "Cautionary Note Regarding Forward-Looking Statements" beginning on page [ ], SkyWater stockholders should carefully consider the following risk factors before deciding whether to vote for the proposal to adopt the Merger Agreement. In addition, you should read and consider the risks associated with each of the businesses of SkyWater and IonQ because these risks will relate to IonQ following the completion of the Mergers. Descriptions of some of these risks can be found in the respective Annual Reports of IonQ and SkyWater on Form 10-K for IonQ's fiscal year ended December 31, 2025 and SkyWater's fiscal year ended December 28, 2025, as such risks may be updated or supplemented in each company's subsequently filed Quarterly Reports on Form 10-Q or Current Reports on Form 8-K, which are incorporated by reference into this proxy statement/prospectus. You should also consider the other information in this document and the other documents incorporated by reference into this document. See "Where You Can Find More Information" beginning on page [ ].

Risks Related to the Mergers

Because the market price of IonQ common stock fluctuates and the Exchange Ratio may be fixed under certain circumstances, and in such circumstances will not be adjusted for stock price changes, SkyWater stockholders cannot be sure of the value of the consideration they will receive.

At the Effective Time, each share of SkyWater common stock, issued and outstanding immediately prior to the Effective Time (other than any Cancelled Shares or Appraisal Shares) will be automatically converted into the right to receive (i) an amount of cash equal to $15.00, without interest, and (ii) such number of shares of IonQ common stock, equal to the Exchange Ratio, plus cash in lieu of any fractional shares to which such share of SkyWater common stock would otherwise be entitled. The "Exchange Ratio" means the following (in each case rounded to four decimals): (A) if the IonQ Trading Price is an amount equal to or less than $37.99, then the Exchange Ratio shall be 0.5265; (B) if the IonQ Trading Price is an amount greater than $37.99 but less than $60.13, then the Exchange Ratio shall be equal to the quotient obtained by dividing $20 by the IonQ Trading Price; and (C) if the IonQ Trading Price is an amount greater than or equal to $60.13, then the Exchange Ratio shall be 0.3326. The "IonQ Trading Price" is the volume-weighted average price (VWAP), rounded to four decimal places, of IonQ common stock on all exchanges as reported by Bloomberg L.P. on the VWAP function for the ticker "[IonQ, Inc. US Equity]" for the 20 full consecutive trading days prior to, but not including, the third business day prior to the Closing Date, calculated from market open (9:30 AM ET) on the first day of the measurement period to market close on the last day of the measurement period (4:00 PM ET).

The market price of IonQ common stock at the time of completion of the Mergers may vary significantly from the market price of IonQ common stock on the date the Merger Agreement was executed and the date of this proxy statement/prospectus. Because the Per Share Stock Consideration is payable (i) in a fixed number of shares of IonQ common stock if the IonQ Trading Price is less than or equal to $37.99 or greater than or equal to $60.13, and (ii) in a floating number of shares of IonQ common stock valuing the stock consideration at $20.00 per share if the IonQ Trading Price is greater than $37.99 and less than $60.13, SkyWater stockholders will not know the actual Exchange Ratio or be able to calculate the market value of the stock consideration they will receive upon completion of the Mergers when they are asked to approve the proposals at the SkyWater special meeting. SkyWater stockholders may receive Per Share Stock Consideration with a value that, at the time received, is less than or more than $20.00 per share for each share of SkyWater common stock exchanged in the Mergers.

Stock price changes may result from a variety of factors, including, among others, general market and economic conditions, changes in IonQ's and SkyWater's respective businesses, operations and prospects, market assessments of the likelihood that the Mergers will be completed, the timing of the Mergers, regulatory considerations and other risk factors set forth or incorporated by reference in this proxy statement/prospectus. Many of these factors are beyond IonQ's and SkyWater's control.

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Under the terms of the Merger Agreement, if the IonQ Trading Price is equal to or less than $37.99, the Exchange Ratio is fixed at 0.5265 shares of IonQ common stock per share of SkyWater common stock, meaning that SkyWater stockholders bear the full downside risk of any decline in IonQ's stock price below the collar floor. Conversely, if the IonQ Trading Price is equal to or greater than $60.13, the Exchange Ratio is fixed at 0.3326, meaning that SkyWater stockholders do not participate in any increase in IonQ's stock price above the collar ceiling. Between those prices, the Exchange Ratio adjusts to deliver $20.00 per share of stock consideration. See "The Merger Agreement-Merger Consideration" beginning on page [ ] for a description of how the Exchange Ratio is calculated.

The Transactions are subject to conditions, some or all of which may not be satisfied or completed on a timely basis, or at all. The Merger Agreement may be terminated in accordance with its terms if such conditions are not completed.

The completion of the Transactions is subject to a number of conditions, including, among others, (i) the receipt of the SkyWater Stockholder Approval, (ii) the receipt of any regulatory approvals required to consummate the Mergers, (iii) the absence of any order or law prohibiting consummation of the Transactions, (iv) the absence of any material adverse effect (as defined in the section titled "The Merger Agreement-Representations and Warranties" beginning on page [ ]) on SkyWater or IonQ since the date of the Merger Agreement, (v) the effectiveness of the registration statement of which this proxy statement/prospectus forms a part and (vi) the authorization for listing on the NYSE of the IonQ common stock to be issued in connection with the Mergers. These conditions make the completion and timing of the Transactions uncertain. For a more detailed discussion regarding conditions to the Transactions, see "The Merger Agreement-Conditions to Completion of the Mergers" beginning on page [ ].

Although IonQ and SkyWater have agreed in the Merger Agreement to use their reasonable best efforts to complete the Mergers as promptly as practicable, many of the closing conditions are not within IonQ's or SkyWater's control, and neither company can predict when or if these conditions will be satisfied. In addition, if the Transactions are not completed by the End Date (which is January 25, 2027), subject to up to two automatic 90-day extensions if on each applicable End Date both such dates all of the closing conditions, except those related to regulatory approvals and governmental orders, have been satisfied or waived, either IonQ or SkyWater may choose not to proceed with the Mergers by terminating the Merger Agreement, and the parties can mutually decide to terminate the Merger Agreement at any time. The failure to satisfy all of the required closing conditions could delay the completion of the Mergers for a significant period of time or prevent them from occurring. Any delay in completing the Mergers could cause IonQ not to realize some or all of the benefits that it expects to achieve if the Mergers are successfully completed within its expected time frame. There can be no assurance that the closing conditions will be satisfied or waived or that the Mergers will be completed. Further, either IonQ or SkyWater may elect to terminate the Merger Agreement in certain other circumstances, as further described in the section titled "The Merger Agreement-Termination of the Merger Agreement" beginning on page [ ].

If the Mergers do not qualify as a "reorganization" under Section 368(a) of the Code, the stockholders of SkyWater may be required to pay substantial U.S. federal income taxes.

The Mergers, taken together, are intended to qualify as a "reorganization" within the meaning of Section 368(a) of the Code. Whether or not the Mergers will qualify as a "reorganization" within the meaning of Section 368(a) of the Code depends on facts that may not be known until after the second to last trading day prior to the Closing Date. The receipt by IonQ or SkyWater of an opinion from counsel as to whether the Mergers will be treated as a "reorganization" within the meaning of Section 368(a) of the Code is not a condition to IonQ's obligation or SkyWater's obligation to complete the Mergers. IonQ and SkyWater have not sought, and will not seek, any ruling from the IRS regarding any matters relating to the Mergers, and as a result, there can be no assurance that the IRS would not assert, or that a court would not sustain, a position contrary to the treatment of the Mergers as a "reorganization" within the meaning of Section 368(a) of the Code. If the Mergers, taken together, do not qualify as a "reorganization" within the meaning of Section 368(a) of the Code or if the IRS or a

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court determines that the Mergers do not qualify as a "reorganization" within the meaning of Section 368(a) of the Code, a U.S. Holder would generally recognize taxable gain or loss upon the exchange of SkyWater common stock for IonQ common stock and cash consideration pursuant to the Mergers. See "The Mergers-Material U.S. Federal Income Tax Consequences" beginning on page [ ].

The Merger Agreement contains provisions that limit SkyWater's ability to pursue alternatives to the Mergers, could discourage a potential competing acquiror of SkyWater from making a favorable alternative transaction proposal and, in specified circumstances, could require SkyWater to pay a Termination Fee to IonQ.

The Merger Agreement contains certain provisions that restrict SkyWater's ability to initiate, solicit, knowingly encourage or facilitate or, subject to certain exceptions, engage in discussions or negotiations with respect to, or approve or recommend, any third-party proposal for an alternative transaction. Further, even if the SkyWater Board withdraws or qualifies its recommendation with respect to the adoption of the Merger Agreement, unless the Merger Agreement has been terminated in accordance with its terms, SkyWater will still be required to submit the Merger Agreement to a vote at the special meeting. In addition, IonQ generally has an opportunity to offer to modify the terms of the Transactions contemplated by the Merger Agreement in response to any third-party alternative transaction proposal before the SkyWater Board may withdraw or qualify its recommendation with respect to the Merger Agreement proposal or otherwise terminate the Merger Agreement.

In some circumstances, upon termination of the Merger Agreement, SkyWater will be required to pay a Termination Fee of $51,573,958.07 to IonQ. Additionally, in the event of a termination following failure to obtain the required regulatory approvals for the Mergers and to resolve or eliminate impediments under Antitrust Laws by the End Date or the Extended End Date, as applicable, SkyWater will be required to issue to IonQ (or a subsidiary), and IonQ (or a subsidiary) will be required to purchase from SkyWater, an aggregate of 2,857,143 newly issued shares of SkyWater common stock for $100,000,000. See the sections titled "The Merger Agreement-Covenant and Agreements-No Solicitation" and "The Merger Agreement-Termination of the Merger Agreement" beginning on pages [ ] and [ ], respectively.

These provisions could discourage a potential third-party acquiror or merger partner that might have an interest in acquiring all or a significant portion of SkyWater or pursuing an alternative transaction from considering or proposing such a transaction, even if it were prepared to pay consideration with a higher per share cash or market value than the per share cash or market value proposed to be received or realized in the Mergers. In particular, the Termination Fee, if applicable, could result in a potential third-party acquiror or merger partner proposing to pay a lower price to the SkyWater stockholders than it might otherwise have proposed to pay absent such a fee.

If the Merger Agreement is terminated and SkyWater determines to seek another business combination, SkyWater may not be able to negotiate a transaction with another party on terms comparable to, or better than, the terms of the Mergers.

The Mergers are subject to the requirements of the HSR Act, and regulatory authorities may impose conditions that could have an adverse effect on SkyWater and/or IonQ following the Mergers or that could delay, prevent or increase the costs associated with completion of the Mergers.

Before the Mergers may be completed, the applicable waiting period (including any extensions thereof) under the HSR Act must have expired or been terminated. In deciding whether to grant the required approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations or other confirmations, the relevant governmental entities may impose requirements, limitations or restrictions on the conduct of the business of IonQ following the Mergers. Under the Merger Agreement, IonQ and SkyWater have agreed to use their respective reasonable best efforts to obtain as promptly as practicable all permits, approvals, clearances, expirations, consents, notices, waivers or terminations of applicable waiting periods, authorizations, qualifications and orders from any governmental authority required to be obtained to consummate the Mergers.

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However, notwithstanding the foregoing, neither IonQ nor SkyWater is required to take, commit or agree to any divestiture or behavioral remedy that (A) is not expressly conditioned on the closing, (B) relates to the operations, activities or businesses of IonQ or its subsidiaries prior to the closing or (C) in the case of a divestiture remedy, would reasonably be expected to have a material adverse effect on SkyWater and its subsidiaries, measured as a whole.

Governmental authorities may also impose conditions, terms, obligations or restrictions in connection with their approval of or consent to the Mergers, and such conditions, terms, obligations or restrictions may delay completion of the Mergers or impose additional material costs on or materially limit IonQ's revenues following the completion of the Mergers. There can be no assurance that governmental authorities will choose not to impose such conditions, terms, obligations or restrictions, and, if imposed, such conditions, terms, obligations or restrictions may delay or lead to the abandonment of the Mergers. At any time before or after consummation of the Mergers, notwithstanding any termination or expiration of the applicable waiting period under the HSR Act, the FTC, the DOJ, or any state attorney general could take such action under U.S. antitrust laws as it deems necessary or desirable in the public interest, including seeking (i) to enjoin the completion of the Mergers, (ii) to require the divestiture of substantial assets of IonQ or SkyWater or their respective subsidiaries, (iii) to require the parties to license rights, to hold separate assets, to terminate existing relationships and contractual rights, or to agree to other restrictions limiting the freedom of action of the parties. Private parties also may bring legal actions under the U.S. antitrust laws under certain circumstances, notwithstanding any termination or expiration of the applicable waiting periods under the HSR Act, seeking similar relief or seeking conditions to the completion of the Mergers. Neither IonQ nor SkyWater can be certain that a challenge to the Mergers on antitrust grounds will not be made, or, if such challenge is made, what the result will be. If any such action is threatened or commenced by the FTC, the DOJ, any state attorney general or any other person, IonQ may not be obligated to consummate the Mergers.

For a more detailed description of the regulatory review process, see the section titled "The Mergers- Regulatory Approvals Required for the Mergers" beginning on page [ ].

Failure to complete the Mergers could negatively affect the stock price and the future business and financial results of SkyWater.

If the Mergers are not completed for any reason, the ongoing business of SkyWater may be adversely affected and, without realizing any of the benefits of having completed the Mergers, SkyWater could be subject to a number of negative consequences, including the following:

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In addition, SkyWater could be subject to litigation related to any failure to complete the Mergers or related to any enforcement proceeding commenced against SkyWater to perform its obligations under the Merger Agreement. If the Mergers are not completed, any of these risks may materialize and may adversely affect SkyWater's businesses, financial condition, financial results and stock price.

Members of the SkyWater Board and management have interests in the Mergers that are different from, or in addition to, those of other stockholders.

In considering whether to adopt the Merger Agreement and approve the Mergers, SkyWater stockholders should recognize that members of management and the SkyWater Board have interests in the Mergers that differ from, or are in addition to, their interests as stockholders of SkyWater.

The executive officers of SkyWater have arrangements with SkyWater that provide for certain severance payments or benefits, accelerated vesting of certain equity-based awards and other rights and other payments or benefits upon completion of the Mergers and/or if their employment or service is terminated under certain circumstances following the completion of the Mergers. The directors of SkyWater have arrangements with SkyWater that provide for accelerated vesting of certain equity-based awards if their service is terminated under certain circumstances following the completion of the Mergers. In addition, the executive officers and directors of SkyWater also have rights to indemnification, advancement of expenses and directors' and officers' liability insurance that will survive the completion of the Mergers. The SkyWater Board was aware of these interests and considered them, among other matters, in approving the Merger Agreement and making its recommendation that the SkyWater stockholders vote "FOR" the Merger Agreement proposal.

These interests are further described in "The Mergers-Interests of Directors and Executive Officers of SkyWater in the Mergers" beginning on page [ ].

The opinion of SkyWater's financial advisor will not reflect changes in circumstances between the signing of the Merger Agreement and the completion of the Mergers.

SkyWater has received an opinion from its financial advisor in connection with the signing of the Merger Agreement, but has not obtained any updated opinion from its financial advisor as of the date of this proxy statement/prospectus. Changes in the operations and prospects of IonQ or SkyWater, general market and economic conditions and other factors that may be beyond the control of IonQ or SkyWater, and on which SkyWater's financial advisor's opinion was based, may significantly alter the value of IonQ or SkyWater or the prices of the shares of IonQ common stock or SkyWater common stock by the time the Mergers are completed. The opinion does not speak as of the time the Mergers will be completed or as of any date other than the date of such opinion. Because SkyWater does not currently anticipate asking its financial advisor to update its opinion, the opinion will not address the fairness of the Merger Consideration from a financial point of view at the time the Mergers are completed. The SkyWater Board's recommendation that SkyWater stockholders vote "FOR" approval of the merger agreement proposal and "FOR" the adjournment proposal, however, is made as of the date of this proxy statement/prospectus.

For a description of the opinion that SkyWater received from its financial advisor, see the section titled "The Mergers-Opinion of SkyWater's Financial Advisor" beginning on page [ ]. A copy of the opinion of Goldman Sachs, SkyWater's financial advisor, is attached as Annex C to this proxy statement/prospectus.

SkyWater may be unable to retain key employees during the pendency of the Mergers.

In connection with the pending Mergers, SkyWater's current and prospective employees may experience uncertainty about their future roles with IonQ following the Mergers, which may materially adversely affect its

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ability to attract and retain key personnel during the pendency of the Mergers. Key employees may depart because of issues relating to the uncertainty and difficulty of integration or a desire not to remain with IonQ following the Mergers. Accordingly, no assurance can be given that SkyWater will be able to retain key employees to the same extent that SkyWater has been able to in the past.

Potential litigation against IonQ and SkyWater could result in substantial costs, an injunction preventing the completion of the Mergers and/or a judgment resulting in the payment of damages.

Securities class action lawsuits and derivative lawsuits are often brought against public companies that have entered into Merger Agreements. Even if such a lawsuit is unsuccessful, defending against these claims can result in substantial costs. An adverse judgment could result in monetary damages, which could have a negative impact on IonQ's and SkyWater's respective liquidity and financial condition.

Stockholders of SkyWater may file lawsuits against IonQ, SkyWater and/or the directors and officers of either company in connection with the Mergers. These lawsuits could prevent or delay the completion of the Mergers and result in significant costs to SkyWater and/or IonQ, including any costs associated with the indemnification of directors and officers. There can be no assurance that any of the defendants will be successful in the outcome of any potential lawsuits.

Completion of the Mergers may trigger change in control or other provisions in certain agreements to which SkyWater is a party, which may have an adverse impact on IonQ's business and results of operations after the Mergers.

The completion of the Mergers may trigger change in control and other provisions in certain agreements to which SkyWater or its subsidiaries are a party. If IonQ and SkyWater are unable to negotiate waivers of those provisions, the counterparties may exercise their rights and remedies under the agreements, potentially terminating the agreements or seeking monetary damages. Even if IonQ and SkyWater are able to negotiate waivers, the counterparties may require a fee for such waivers or seek to renegotiate the agreements on terms less favorable to SkyWater or IonQ following the Mergers.

The shares of IonQ common stock to be received by SkyWater stockholders upon completion of the Mergers will have different rights from shares of SkyWater common stock.

Upon completion of the Mergers, SkyWater stockholders will no longer be stockholders of SkyWater but will instead become stockholders of IonQ, and their rights as IonQ stockholders will be governed by the terms of IonQ's certificate of incorporation, as amended ("IonQ's Certificate of Incorporation"), and IonQ's bylaws, as amended ("IonQ's Bylaws"). The terms of IonQ's Certificate of Incorporation and IonQ's Bylaws are in some respects materially different than the terms of SkyWater's certificate of incorporation ("SkyWater's Certificate of Incorporation"), and SkyWater's Bylaws, which currently govern the rights of SkyWater stockholders. See "Comparison of Rights of Stockholders of IonQ and SkyWater" beginning on page [ ] for a discussion of the different rights associated with shares of SkyWater common stock and shares of IonQ common stock.

SkyWater stockholders will have a significantly reduced ownership and voting interest after the Mergers and will exercise less influence over the policies of IonQ following the Mergers than they now have on the policies of SkyWater.

IonQ stockholders currently have the right to vote in the election of the IonQ board of directors (the "IonQ Board") and on other matters affecting IonQ. SkyWater stockholders currently have the right to vote in the election of the SkyWater Board and on other matters affecting SkyWater. Immediately after the Mergers are completed, it is expected that current IonQ stockholders will own approximately [ ]% of the shares of outstanding common stock of IonQ following the Mergers, and current SkyWater stockholders will own approximately [ ]% of the common stock outstanding of IonQ following the Mergers. As a result, current

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SkyWater stockholders will have significantly less influence on the policies of IonQ than they now have on the policies of SkyWater.

Risks Relating to IonQ After Completion of the Mergers

IonQ may not achieve the intended benefits and the Mergers may disrupt its current plans or operations.

There can be no assurance that IonQ will be able to successfully integrate SkyWater's assets or otherwise realize the expected benefits of the Mergers. Difficulties in integrating SkyWater into IonQ may result in IonQ performing differently than expected or in operational challenges or in the failure to realize anticipated benefits in the expected time frame or at all. The integration of the two companies may result in material challenges, including the diversion of management's attention from ongoing business concerns; retaining key management and other employees; retaining or attracting business and operational relationships; the possibility of faulty assumptions underlying expectations regarding the integration process and associated expenses; consolidating corporate and administrative infrastructures; coordinating geographically separate organizations; unanticipated issues in integrating information technology, communications and other systems; as well as potential unknown liabilities, unforeseen expenses relating to integration or delays associated with the acquisition.

The market price of IonQ's common stock after the Mergers may be affected by factors different from those affecting the price of IonQ or SkyWater common stock before the Mergers.

Upon completion of the Mergers, holders of IonQ common stock and SkyWater common stock will be holders of IonQ common stock. As the businesses of IonQ and SkyWater are different, the results of operations as well as the price of IonQ's common stock may in the future be affected by factors different from those factors affecting IonQ and SkyWater as independent standalone companies. IonQ following the Mergers will face additional risks and uncertainties that IonQ or SkyWater may currently not be exposed to as independent companies.

The market price of IonQ's common stock may decline as a result of the Mergers.

The market price of IonQ common stock may decline as a result of the Mergers if, among other things, it is unable to achieve the expected benefits of the Mergers, if the Mergers are not completed within the anticipated time frame or if the transaction costs related to the Mergers are greater than expected. The market price also may decline if IonQ does not achieve the perceived benefits of the Mergers as rapidly or to the extent anticipated by financial or industry analysts or if the effect of the Mergers on IonQ's financial position, results of operations or cash flows is not consistent with the expectations of financial or industry analysts.

The completion of the Mergers may result in a loss of customers, distributors, suppliers, vendors, landlords and other business partners and may result in the termination of existing contracts.

Following the Mergers, some of the customers, distributors, suppliers, vendors, landlords and other business partners of SkyWater may terminate or scale back their current or prospective business relationships with IonQ. Some customers may not wish to source a larger percentage of their needs from a single company. In addition, SkyWater has contracts with customers, distributors, suppliers, vendors, landlords and other business partners that may require it to obtain consents from these other parties in connection with the Mergers, which may not be obtained on favorable terms or at all. If relationships with customers, distributors, suppliers, vendors, landlords and other business partners are adversely affected by the Mergers, or if IonQ, following the Mergers, loses the benefits of the contracts of SkyWater, IonQ's business and financial performance could suffer.

Risks Related to the Voting Agreement

Certain SkyWater stockholders, collectively holding approximately 19.87% of SkyWater's outstanding voting power as of January 25, 2026, have entered into a Voting Agreement with IonQ pursuant to which they

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have agreed, among other things, to vote their shares in favor of the adoption of the Merger Agreement. While the Voting Agreement reduces the number of additional votes needed to obtain the SkyWater Stockholder Approval, it does not guarantee that the requisite vote will be obtained. The Voting Agreement terminates automatically upon, among other things, the termination of the Merger Agreement in accordance with its terms, a change in the SkyWater recommendation or an Adverse Amendment.

Other Risk Factors of IonQ and SkyWater

IonQ's and SkyWater's businesses are and will be subject to the risks described above. In addition, IonQ and SkyWater are and will continue to be subject to the risks described in IonQ's and SkyWater's respective Annual Reports on Form 10-K for the fiscal years ended December 31, 2025, and December 28, 2025, respectively, as updated by subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, all of which are filed with the SEC and incorporated by reference into this proxy statement/prospectus. For the location of information incorporated by reference into this proxy statement/prospectus, see "Where You Can Find More Information" beginning on page [ ].

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THE MERGERS

The following is a discussion of the Mergers and the material terms of the Merger Agreement between IonQ and SkyWater. You are urged to read the Merger Agreement carefully and in its entirety. A copy of the Merger Agreement is attached as Annex A to this proxy statement/prospectus and incorporated by reference herein. This summary does not purport to be complete and may not contain all of the information about the Mergers that is important to you. This section is not intended to provide you with any factual information about IonQ or SkyWater. Such information can be found elsewhere in this proxy statement/prospectus and in the public filings IonQ and SkyWater make with the SEC that are incorporated by reference into this document, as described in "Where You Can Find More Information" beginning on page [ ].

Background of the Mergers

The SkyWater Board and management periodically review and assess SkyWater's results of operations, financial position, share price, business strategy and opportunities and risks, as well as the trends and conditions affecting SkyWater's industry and business generally. Such assessments include periodic meetings or consultations with third-party advisors, as well as consideration of a wide range of potential strategic and financial alternatives, including acquisitions, financing transactions, investments in SkyWater and business combinations, with a view to maximizing stockholder value.

SkyWater began pursuing IonQ to become a customer of SkyWater in 2024. Following that time, SkyWater executives and IonQ executives met periodically to discuss a potential commercial relationship, independent of the Transactions and the parties held periodic technical and operational meetings at SkyWater facilities between October 2025 and February 2026. These commercial discussions were conducted separately from, and were not conditioned on, the Transactions. As described below, IonQ first raised strategic alternatives in late November 2025, and those discussions proceeded on a separate track.

On November 23, 2025, Niccolo de Masi, IonQ's Chairman and Chief Executive Officer, and John Sakamoto, SkyWater's President and Chief Operating Officer, had a telephone call regarding the potential commercial relationship between IonQ and SkyWater, during which they discussed the possibility of a development partnership between the companies for SkyWater to provide Advanced Technology Services ("ATS") to IonQ and Mr. de Masi raised the potential for IonQ to make an investment in SkyWater. On November 25, 2025, Mr. de Masi and Mr. Sakamoto had a telephone call on the same topics and Mr. de Masi requested a further call with Thomas Sonderman, SkyWater's Chief Executive Officer.

On November 26, 2025, Mr. de Masi met virtually with Mr. Sonderman, Mr. Sakamoto and Steve Manko, SkyWater's Chief Financial Officer, and expressed that IonQ had an interest in exploring a broader strategic partnership with SkyWater, including potentially a joint venture with SkyWater, a direct investment in SkyWater, or an acquisition of SkyWater.

On November 26, 2025, Loren Unterseher, a SkyWater director and a significant holder of SkyWater common stock, also had a telephone discussion with Mr. de Masi regarding IonQ's interest in acquiring SkyWater.

On November 28, 2025, Mr. de Masi and Mr. Sonderman had a telephone call in which Mr. de Masi stated that IonQ intended to provide SkyWater with a proposal to acquire SkyWater, subject to a discussion with the IonQ Board.

On December 3, 2025, Mr. de Masi and Mr. Sonderman had a telephone call in which Mr. de Masi informed Mr. Sonderman that the IonQ Board had approved IonQ making an offer to acquire SkyWater and that Mr. de Masi expected to provide a formal proposal on December 4, 2025.

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In the morning on December 4, 2025, Mr. de Masi, on behalf of the IonQ Board, delivered to Timothy Baxter, SkyWater's independent Chairman of the Board, a non-binding written proposal for IonQ to acquire 100% of the outstanding shares of SkyWater common stock. IonQ proposed that SkyWater stockholders would receive $12.50 per share in cash and $12.50 per share in IonQ common stock, or $25 per share of SkyWater stock in total. The amount of IonQ common stock would be based on the IonQ VWAP prior to signing a definitive agreement and be subject to a symmetrical 10% collar based on the IonQ VWAP for the 10 trading days prior to closing. The proposal was subject to completion of due diligence. The proposal indicated that the cash portion of the purchase price would be funded entirely with cash on IonQ's balance sheet, and the definitive agreement would not include any financing condition. The proposal also stated that IonQ was only prepared to move forward with a transaction on an exclusive basis.

In the evening on December 4, 2025, the SkyWater Board held a special meeting by video conference, together with SkyWater's management. Among other things, the SkyWater Board discussed Skywater's current strategic plan and recent developments with that plan. The SkyWater Board also reviewed the terms of the IonQ proposal and discussed considerations relating to a potential acquisition of SkyWater by IonQ, including SkyWater's long-term growth opportunities pursuant to SkyWater's current strategic plan compared to the IonQ proposal. Messrs. Sonderman, Unterseher and Sakamoto also informed the SkyWater Board of and reviewed with the SkyWater Board the prior discussions each of them had with IonQ representatives. Christopher Hilberg, SkyWater's Chief Risk and Compliance Officer, General Counsel and Secretary, reviewed with the SkyWater Board its fiduciary duties in connection with a potential sale or merger transaction or other strategic alternatives. The SkyWater Board discussed engaging a financial advisor, including potential options with the requisite industry expertise, to assist it in evaluating the IonQ proposal and potential strategic alternatives. Following that discussion, the SkyWater Board determined to engage Goldman Sachs & Co. Inc. ("Goldman Sachs") as financial advisor because it is an internationally recognized investment banking firm that has substantial experience in transactions similar to the Transactions and authorized management to engage Goldman Sachs to act as financial advisor to SkyWater, subject to confirmation that Goldman Sachs did not have disabling conflicts and negotiating with Goldman Sachs an appropriate engagement letter.

On December 7, 2025, Paul Dacier, IonQ's Chief Legal Officer, Corporate Secretary and Chief Administrative Officer sent Mr. Hilberg a draft mutual confidentiality agreement to facilitate discussions and the disclosure of information between SkyWater and IonQ. IonQ, SkyWater, IonQ's outside legal counsel, Paul, Weiss, Rifkind, Wharton & Garrison LLP ("Paul, Weiss"), and SkyWater's regular outside legal counsel, Foley & Lardner LLP ("Foley"), negotiated, and the parties executed, a mutual confidentiality agreement on December 21, 2025. This confidentiality agreement has a two-year term expiring on December 21, 2027, subject to earlier termination upon closing of the Transactions. The confidentiality agreement contained, among other things, a one-year mutual "standstill" provision with a customary "fall-away" provision that would render the standstill restrictions inapplicable if SkyWater entered into a definitive agreement involving all or a majority of the voting securities or consolidated assets of SkyWater or a third party commenced a tender or exchange offer for all or a majority of SkyWater's outstanding voting securities and SkyWater or the SkyWater Board recommended or accepted such offer or failed to recommend that its stockholder reject such offer. The confidentiality agreement did not include a "don't ask, don't waive" provision. In addition, notwithstanding the standstill restrictions, the confidentiality agreement permitted IonQ to make confidential offers or proposals to SkyWater, provided that such communications were made in a manner that would not reasonably be expected to require either party to make public disclosure under applicable law or regulation.

In the evening on December 9, 2025, Mr. de Masi met with Mr. Baxter and Mr. Sonderman for a dinner at which there was discussion on the background of IonQ and the quantum industry, potential synergies in connection with an acquisition of SkyWater by IonQ and next steps regarding the process for a potential acquisition of SkyWater by IonQ.

On December 10, 2025, Mr. de Masi met with Mr. Unterseher for a breakfast at which there was discussion on the background of IonQ and SkyWater and the potential strategic fit of SkyWater with IonQ.

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On December 11, 2025 the SkyWater Board met in person at a regularly scheduled meeting, with representatives of SkyWater management, Goldman Sachs and Foley present. Foley provided an overview of the SkyWater Board's fiduciary duties in connection with a potential sale or merger transaction or other strategic alternatives, as well as public disclosure considerations relating to such a transaction. Representatives of Goldman Sachs reviewed with the SkyWater Board IonQ's proposal and provided an overview of IonQ and its business and financial performance. Representatives of Goldman Sachs also discussed with the SkyWater Board considerations for evaluating value and strategic alternatives, including a potential process to evaluate the IonQ proposal and potential responses to IonQ. Messrs. Baxter, Sonderman and Unterseher also reviewed with the SkyWater Board the discussions each of them had with IonQ representatives. During the meeting, the SkyWater Board also received an update from management on SkyWater's strategic plan and reviewed SkyWater's annual operating plan. The SkyWater Board reviewed the current strategic plan and considerations associated with pursuing that plan as a standalone company compared to engaging with IonQ regarding its proposal. The SkyWater Board also discussed IonQ's relationship with SkyWater as a customer and other potential strategic alternatives. The SkyWater Board directed representatives of Goldman Sachs, after it completed further review of the IonQ proposal, to inform IonQ's advisors that SkyWater was prepared to continue discussions, but that IonQ would need to provide an improved proposal with respect to both price and consideration mix after conducting due diligence.

At the December 11, 2025 SkyWater Board meeting, Mr. Hilberg also reviewed with the SkyWater Board a proposed engagement letter that management had negotiated with Goldman Sachs and the SkyWater Board was informed that Goldman Sachs had not been engaged by IonQ or its affiliates to provide financial advisory or underwriting services. On December 11, 2025, SkyWater entered into the engagement letter with Goldman Sachs.

On December 11, 2025 Mr. Unterseher had a telephone call with Mr. de Masi, in which Mr. Unterseher informed Mr. de Masi that the SkyWater Board was reviewing IonQ's proposal and had retained Goldman Sachs as its financial advisor.

On December 12, 2025, Mr. Baxter informed Mr. de Masi in a telephone call that the IonQ proposal had been reviewed with the SkyWater Board, SkyWater had engaged Goldman Sachs as financial advisor and SkyWater and Goldman were continuing to review the IonQ proposal. Mr. Baxter suggested Goldman Sachs connect with IonQ's financial advisor. Mr. de Masi informed Mr. Baxter that IonQ had engaged Cantor Fitzgerald & Co. ("Cantor Fitzgerald") as its financial advisor and that Mr. de Masi would introduce Cantor Fitzgerald to Goldman Sachs.

On December 14, 2025, representatives of Goldman Sachs and Cantor Fitzgerald held a telephone call in which representatives of Goldman Sachs noted that Goldman Sachs was continuing to review the IonQ proposal and asked Cantor Fitzgerald for the basis for the cash-stock mix of consideration. Cantor Fitzgerald noted that SkyWater stockholders should find equity consideration consisting of IonQ's common stock attractive because of the upside growth potential.

On December 16, 2025, Mr. Baxter, Mr. Unterseher, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs met virtually to discuss Goldman Sachs' further review of the IonQ proposal and the potential response to IonQ. Mr. Baxter confirmed the instructions the SkyWater Board had provided to Goldman Sachs at its December 11, 2025 meeting, instructing Goldman Sachs to advise IonQ that SkyWater was prepared to continue discussions, but that IonQ would need to provide an improved proposal with respect to both price and consideration mix after conducting due diligence.

On December 17, 2025, representatives of Goldman Sachs informed Cantor Fitzgerald in a telephone call that SkyWater was taking the IonQ proposal seriously and continued to be open to engaging with IonQ but that SkyWater was rejecting the IonQ proposal on its current terms and that the SkyWater Board expected IonQ to submit an improved proposal with respect to both price and consideration mix after conducting due diligence.

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Representatives of Goldman Sachs explained that the SkyWater Board preferred cash consideration to stock consideration because of the greater certainty of value from cash. Representatives of Goldman Sachs also informed Cantor Fitzgerald that SkyWater was working on a data room to contain information for due diligence purposes but that IonQ needed to provide its due diligence requests.

On December 18, 2025, Cantor Fitzgerald provided Goldman Sachs with IonQ's initial due diligence request list and a list of initial key diligence items. On December 21, 2025, Cantor Fitzgerald provided Goldman Sachs with supplemental updates to the initial due diligence request list and list of initial key diligence items, as well as requests for due diligence calls to be held with SkyWater representatives.

On December 22, 2025, Mr. de Masi spoke with Mr. Baxter on a telephone call and asked why SkyWater would not come back with a counterproposal to the IonQ proposal with economic terms on which the parties could agree on a transaction. Mr. Baxter informed Mr. de Masi that SkyWater had provided its position on the IonQ proposal through Goldman Sachs on the December 17, 2025 call with Cantor Fitzgerald. They also discussed SkyWater's strategic plan and IonQ's prospective plans for operating SkyWater post-closing of a transaction.

On December 22, 2025, Mr. de Masi spoke with Mr. Sonderman regarding the commercial engagement between SkyWater and IonQ. Mr. de Masi also discussed with Mr. Sonderman IonQ's prospective plans for operating SkyWater post-closing of a transaction and requested that SkyWater provide further information on the investment required to execute its strategic plan.

On December 22, 2025, representatives of Goldman Sachs held a telephone call with Cantor Fitzgerald and reiterated that SkyWater had rejected the IonQ proposal but that SkyWater was open to engaging with IonQ if IonQ provided SkyWater with an improved proposal with respect to both price and consideration mix after completing due diligence. On the call, Cantor Fitzgerald also requested an update from representatives of Goldman Sachs on when virtual data room access would be provided to IonQ and its advisors.

On December 23, 2025, a virtual data room containing SkyWater information was made available to IonQ and its advisors for due diligence review purposes. Thereafter, IonQ and its representatives conducted due diligence with respect to SkyWater, engaging with SkyWater and its representatives as part of that process.

On January 4, 2026, Mr. de Masi sent a message Mr. Baxter that, among other things, expressed concern about the speed with which SkyWater was responding to due diligence requests, stated that IonQ would not be prepared to proceed with a transaction unless a definitive agreement was entered into no later than January 30, 2026, noted that the recent increase in SkyWater stock price has no bearing on the price IonQ is prepared to pay in a transaction, and reiterated the IonQ was only prepared to move forward with a transaction with SkyWater on an exclusive basis.

Over the course of January 5, 2026 and January 6, 2026, Mr. Baxter, Dennis Goetz (a SkyWater independent director and chair of the Audit Committee), Mr. Unterseher, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs and Foley met virtually to discuss a response to Mr. de Masi's message and due diligence progress and timing of a potential transaction. Mr. Goetz and Mr. Unterseher had previously requested to participate on internal meetings Mr. Baxter had with SkyWater management and representatives of Goldman Sachs and Foley to bring their subject matter experience and support the transaction process, and the SkyWater Board was aware Mr. Goetz and Mr. Unterseher participated in such meetings. The group also discussed other potential purchasers of SkyWater and reviewed options for approaching potential purchasers other than IonQ. Among other things, the group discussed regulatory and national security concerns that would make it difficult for certain potential purchasers to complete a transaction to acquire SkyWater, the low probability of a potential purchaser being able or willing to make an economic proposal on terms superior to IonQ's proposal, and IonQ's consistent position that it would only continue discussions with SkyWater on an exclusive basis.

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On January 6, 2026, Mr. Baxter and Mr. de Masi spoke on a telephone call. Among other things, they discussed the importance of exclusivity to IonQ, the progress and timing of due diligence with respect to SkyWater and its business and the importance of accelerating that process, SkyWater's management forecast and related due diligence and recent upward movement in the trading price of SkyWater's common stock and how that might impact the pricing of the Transactions. Following the call, Mr. de Masi sent a message to Mr. Baxter which provided a timeline for Paul, Weiss to deliver a draft Merger Agreement to SkyWater and its representatives later that week and confirmed that IonQ would provide a revised offer to SkyWater.

On January 8, 2026, Mr. Unterseher and Mr. de Masi spoke on a telephone call. Mr. de Masi confirmed that IonQ would be revising its proposal. In the call, Mr. de Masi inquired about the preferences of the SkyWater Board as to the mix of cash and stock consideration. Mr. Unterseher reiterated the SkyWater Board's position that it favored increased cash consideration to provide greater certainty of value to SkyWater's stockholders but did not provide further guidance. Mr. Unterseher suggested IonQ should put forth its best offer and that the SkyWater Board would promptly review the revised proposal.

On January 9, 2026, Mr. de Masi, on behalf of the IonQ Board, delivered to Mr. Baxter a revised written, non-binding proposal to acquire 100% of the outstanding shares of SkyWater common stock. Under the revised proposal, SkyWater stockholders would receive $32.50 per share of SkyWater common stock in total, consisting of $14.00 per share in cash (43% of the total) and $18.50 per share in IonQ common stock (57% of the total). The revised proposal included a wider symmetrical collar of 12% and reiterated IonQ's position that it was prepared to move forward with a transaction only on an exclusive basis.

On January 10, 2026, Paul, Weiss sent initial drafts of the Merger Agreement and Voting Agreement to Foley. Foley shared the drafts with SkyWater management, members of the SkyWater Board, including Mr. Unterseher, who is a party to the Voting Agreement, Dorsey & Whitney LLP, counsel to Mr. Unterseher and his affiliates that are parties to the Voting Agreement ("Dorsey"), and representatives of Goldman Sachs. Among other terms, the draft Merger Agreement provided for a termination fee of 4.0% of SkyWater's fully diluted equity value payable by SkyWater if the Merger Agreement was terminated (1) by IonQ following a Change of SkyWater Recommendation, (2) by SkyWater to accept a Superior Proposal, or (3) under certain other circumstances after which SkyWater signs an agreement with respect to, or consummates, an acquisition proposal within 12 months of termination. The draft Merger Agreement also required that each party use its reasonable best efforts to secure regulatory clearances, but disclaimed any IonQ obligation to make any divestitures, licensing arrangements or similar restrictions. Among other terms, the draft Voting Agreement provided that the Voting Agreement would not terminate upon a change in the recommendation of the SkyWater Board to stockholders with respect to the vote to approve the Merger Agreement and Mergers and also included a "clawback" provision under which the stockholder parties to the Voting Agreement would be required to pay to IonQ 90% of any amount in excess of the Merger Consideration paid as to the stockholder parties as a result of any Acquisition Proposal announced or consummated within 12 months of the termination of the Merger Agreement.

On January 10 and 11, 2026, Mr. Baxter, Mr. Unterseher, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs and Foley met virtually to discuss IonQ's revised price and collar proposal and issues with the drafts of the Merger Agreement, including with respect to termination fees and required efforts to obtain regulatory approvals, and the Voting Agreement.

On January 12, 2026, the SkyWater Board held a special meeting by video conference, together with SkyWater's management and representatives of Goldman Sachs and Foley, to review IonQ's revised proposal and the draft of the Merger Agreement. Representatives of Goldman Sachs reviewed with the SkyWater Board the status of discussions with IonQ and summarized the economic terms of IonQ's revised proposal, and discussed the implications of the proposed mix of cash and stock consideration, including operation of the collar. Foley also presented a summary of the material terms of the draft Merger Agreement and draft Voting Agreement and recommended changes to the draft Merger Agreement and discussed fiduciary duty considerations. The SkyWater Board and advisors discussed whether to approach other potential purchasers, in

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addition to IonQ, considering among other things, the regulatory or national security concerns related to certain potential purchasers, including those with non-U.S. ownership, the low probability of a potential purchaser being able or willing to make an economic proposal on terms superior to IonQ's revised proposal, and IonQ's stated expectation of exclusivity, including that IonQ would not continue negotiations if SkyWater approached or entertained offers or inquiries from other potential purchasers. The SkyWater Board and management also discussed SkyWater's long-term strategic plan, risks related to remaining an independent public company and risks of the Mergers, including risks that could arise between signing the Merger Agreement and closing of the Mergers. Among other things, the SkyWater Board discussed its desire to increase the portion of the Merger Consideration that would be payable in cash and to expand the symmetrical collar, to increase the certainty of consideration for the SkyWater stockholders. The SkyWater Board authorized Mr. Baxter to communicate to IonQ a counterproposal with specific terms for price, mix of consideration and collar, as well as authorized Mr. Baxter to engage in further discussions with IonQ regarding the economic and other terms of a Merger Agreement, subject to approval by the SkyWater Board.

Later on January 12, 2026, Mr. Baxter, on behalf of the SkyWater Board, delivered a written counterproposal to Mr. de Masi, as representative of IonQ and the IonQ Board. Under SkyWater's counterproposal, SkyWater stockholders would receive $34.00 in total per share of SkyWater common stock, consisting of $22.10 per share in cash (65% of the total) and $11.90 per share in IonQ common stock (35% of the total). The counterproposal increased the symmetrical collar from 12% to 25%, with the collar to be based on a 20-day VWAP. Mr. Baxter also stated that SkyWater would require reciprocal due diligence for SkyWater and its advisors to evaluate IonQ's financial condition, operational capabilities and strategic plans.

On January 13, 2026, Mr. de Masi responded to Mr. Baxter and the SkyWater counterproposal requesting SkyWater provide revised drafts of the Merger Agreement and Voting Agreement. Mr. Baxter responded that SkyWater's legal team was reviewing the draft agreements and working on revised drafts that would be in a position to send later in the week if the parties were able to reach an agreement on financial terms.

On January 13, 2026, Mr. Baxter, Mr. Unterseher, Mr. Goetz, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs and Foley met virtually to discuss revisions to the draft Merger Agreement, including with respect to termination fees and required efforts to obtain regulatory approvals.

On January 14, 2026, Foley and Dorsey met virtually to discuss proposed changes to the Voting Agreement and the process for conveying combined comments to Paul, Weiss.

On January 15, 2026, Foley sent Paul, Weiss a revised draft of the Merger Agreement. Among other terms, the draft Merger Agreement reflected the economic terms from SkyWater's January 12, 2026 proposal. The draft Merger Agreement lowered the termination fee payable by SkyWater from 4.0% to 2.0% of SkyWater's fully diluted equity value. The draft Merger Agreement also required that each party use its reasonable best efforts to secure regulatory clearance, and required IonQ to make divestitures, licensing arrangements or similar restrictions and litigate if necessary to clear regulatory approvals. The draft Merger Agreement also provided for a reverse termination fee of 7.5% of SkyWater's fully diluted equity value payable by IonQ if the Merger Agreement were terminated as a result of a failure to obtain regulatory approval. Also on January 15, 2026, Foley sent Paul, Weiss a revised draft Voting Agreement that, among other things, expanded the events triggering termination of the Voting Agreement to include a change in the recommendation of the SkyWater Board to stockholders with respect to the vote to approve the Merger Agreement and Mergers and deleted the "clawback" provision.

On January 15, 2026, Paul, Weiss responded to Foley in a telephone call regarding the revised draft of the Merger Agreement. Paul, Weiss communicated that IonQ would agree to a termination fee payable by SkyWater of 3.0% of SkyWater's fully diluted equity value, that IonQ would propose a compromise on required efforts to obtain regulatory approvals and that a reverse termination fee payable by IonQ would not be acceptable to IonQ.

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Later on January 15, 2026, Mr. de Masi, on behalf of the IonQ Board, sent Mr. Baxter a further revised written proposal with respect to price, consideration mix and collar terms. Under IonQ's counterproposal, SkyWater stockholders would receive $35.00 in total for each share of SkyWater common stock, consisting of $15.00 per share in cash (approximately 43% of the total) and $20.00 per share in IonQ common stock (approximately 57% of the total). The counterproposal included a 15% symmetrical collar.

On January 16, 2026, Mr. Baxter, Mr. Unterseher, Mr. Goetz, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs and Foley met virtually to discuss the revised IonQ proposal delivered on January 15, 2026.

Later on January 16, 2026, Cantor Fitzgerald informed SkyWater and representatives of Goldman Sachs that IonQ's January 15, 2026 proposal reflected IonQ's "best and final" offer with respect to the offer price and consideration mix.

On January 18, 2026, Paul, Weiss sent revised drafts of the Merger Agreement and Voting Agreement to Foley and Dorsey. Among other terms, the draft Merger Agreement reflected the economic terms from IonQ's January 15, 2026 proposal. It also provided for a termination fee of 3.0% of SkyWater's fully diluted equity value payable by SkyWater. The draft Merger Agreement also required that each party use its reasonable best efforts to secure regulatory clearance, including an obligation for IonQ to agree to make divestitures of SkyWater's operations if such divestitures would not have a material adverse effect on SkyWater, IonQ to agree to behavioral and conduct remedies with respect to SkyWater's operations, and IonQ and SkyWater to litigate if necessary to clear regulatory approvals. The Merger Agreement draft did not include a reverse termination fee payable by IonQ in connection with a failure to obtain regulatory approval. The draft Voting Agreement did not include a termination event upon a change in the recommendation of the SkyWater Board to stockholders with respect to the vote to approve the Merger Agreement and Mergers.

Later on January 18, 2026, Mr. Baxter, Mr. Unterseher, Mr. Goetz, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs and Foley met virtually to discuss a response to IonQ's most recent proposal with respect to price, consideration mix and collar terms and the revised draft of the Merger Agreement.

On January 19, 2026, Mr. Baxter delivered a written counterproposal to Mr. de Masi. SkyWater agreed to IonQ's "best and final" offer price and consideration mix, contingent on IonQ's acceptance of a 25% symmetrical collar based on a 20-day VWAP, a reduced termination fee payable by SkyWater of 2.5% of SkyWater's fully diluted equity value, and a reverse termination fee payable by IonQ of 6.75% of SkyWater's fully diluted equity value, as well as completion of SkyWater's reverse due diligence on IonQ's business.

On January 19, 2026, representatives of Goldman Sachs provided Cantor Fitzgerald with SkyWater's due diligence request list for reverse due diligence on IonQ, as well as a request for a due diligence call to be held with IonQ representatives. On January 22, 2026, a virtual data room containing IonQ information was made available to SkyWater and its advisors for due diligence review purposes. Thereafter, SkyWater and its representatives conducted due diligence with respect to IonQ, engaging with IonQ and its representatives as part of that process.

On January 20, 2026, Paul, Weiss delivered to Foley in a telephone call the following "package" proposal of IonQ addressing the key open items in the draft Merger Agreement: (1) a collar range of $42.50 to $61.15, or representing an approximately 18% symmetrical collar around a midpoint of IonQ's 10-day VWAP on January 20,2026; (2) the termination fee payable by SkyWater of 2.86% of SkyWater's fully diluted equity value; (3) no reverse termination fee payable by IonQ and (4) in the event of regulatory approval failure, IonQ would purchase $100 million of SkyWater common stock at $35.00 per share.

On January 20, 2026, Mr. Baxter, Mr. Unterseher, Mr. Goetz, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs and Foley met virtually to discuss a response to IonQ's "package" proposal.

On January 20, 2026, Foley sent Paul, Weiss a revised draft of the Merger Agreement. Also on January 20, 2026, Foley sent Paul, Weiss a revised draft Voting Agreement that, among other things, provided for the

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termination events under the Voting Agreement to include a change in the recommendation of the SkyWater Board to stockholders with respect to the vote to approve the Merger Agreement and Mergers.

On January 21, Mr. Baxter had a telephone call with Mr. de Masi in which Mr. Baxter noted that he would discuss with the SkyWater Board accepting the termination fee payable by SkyWater at 2.86% of SkyWater's fully diluted equity value and no reverse termination fee payable by IonQ, but in the event of regulatory approval failure, IonQ would invest $100 million in SkyWater common stock at $35.00 per share. However, with respect to the collar, Mr. Baxter conveyed that SkyWater continued to need a 25% symmetrical collar based on a 20-day VWAP. Mr. de Masi countered with an 18% symmetrical collar and, after discussion, Mr. Baxter agreed he would discuss with the SkyWater Board a 22% symmetrical collar based on a 20-day VWAP.

On January 21, 2026, the SkyWater Board held a special meeting by video conference, together with SkyWater's management and representatives of Goldman Sachs and Foley, to review IonQ's most recent proposal. Representatives of Goldman Sachs reviewed the Merger Consideration and other terms of IonQ's proposal, which reflected $35.00 in total Merger Consideration for each share of SkyWater common stock, consisting of $15.00 per share in cash (approximately 43% of the total) and $20.00 per share in IonQ common stock (approximately 57% of the total), subject to a 22% symmetrical collar based on 20-day VWAP. Goldman Sachs's presentation included a history of the changes in the Merger Consideration and other key terms over course of the negotiations, the changes in the trading prices of IonQ common stock and SkyWater common stock, respectively, during the negotiation period, and the implied premiums and multiples that the Merger Consideration represented. Foley also presented an updated summary of the material terms of the draft Merger Agreement and draft Voting Agreement, which summary was circulated to the SkyWater Board in advance of the meeting. Among other terms, Foley discussed the termination fee payable by SkyWater at 2.86% of SkyWater's fully diluted equity value and the requirement that IonQ would invest $100 million in SkyWater common stock at $35.00 per share in the event of regulatory approval failure. The SkyWater Board and advisors again discussed whether to approach other potential purchasers, in addition to IonQ, considering among other things, regulatory or national security concerns with other potential purchasers, the low probability of a potential purchaser being able or willing to make a superior economic proposal compared to IonQ's, the risk IonQ would rescind its proposal if SkyWater approached other potential purchasers, and that, given the significant portion of stock in the mix of Merger Consideration, the SkyWater stockholders would continue to be able to participate in the combined company after closing of the Mergers. The SkyWater Board ultimately determined that it would be in the best interest of SkyWater and its stockholders to not approach other potential purchasers. After discussion, the SkyWater Board expressed support for continuing to pursue the transaction on the terms discussed and directed management and SkyWater's advisors to continue to finalize definitive agreements.

On January 22, 2026, Paul, Weiss sent Foley a further revised draft of the Merger Agreement, consistent with the above.

Following a discussion between Paul, Weiss and Dorsey to discuss the Voting Agreement, on January 22, 2026, Paul, Weiss sent Foley and Dorsey a further revised draft of the Voting Agreement. The draft Voting Agreement did not include a termination event upon a change in the recommendation of the SkyWater Board to stockholders with respect to the vote to approve the Merger Agreement and Mergers. On January 24, 2026 the parties and counsel continued to discuss and exchange drafts of the Voting Agreement, with IonQ agreeing to include a termination event upon a change in the recommendation of the SkyWater Board to stockholders with respect to the vote to approve the Merger Agreement and Mergers.

On January 22, 2026, Foley sent Paul, Weiss a draft of SkyWater's disclosure schedules with respect to the Merger Agreement.

On January 23, 24 and 25, 2026, Mr. Baxter, Mr. Unterseher, Mr. Manko, Mr. Hilberg and representatives of Goldman Sachs and Foley met virtually to discuss the collar. The parties and counsel also met virtually and corresponded regarding the collar, before ultimately agreeing to a collar fixed on January 23, 2026 of $37.99 to $60.13.

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On January 24 and January 25, 2026, the parties and counsel continued to discuss and exchange drafts of the Merger Agreement.

On January 24, 2026, Paul, Weiss sent Foley comments on Foley's draft of SkyWater's disclosure schedules with respect to the Merger Agreement. On January 24, 2026, Paul, Weiss sent Foley a draft of IonQ's disclosure schedules with respect to the Merger Agreement.

On January 24 and January 25, 2026, the parties and counsel continued to discuss and exchange drafts of the disclosure schedules, including a series of discussions regarding exceptions to covenants restricting SkyWater's activities between signing the Merger Agreement and closing the Mergers.

On January 25, 2026, Paul, Weiss, Foley and Dorsey exchanged final drafts of the Merger Agreement, Voting Agreement and disclosure schedules.

On January 25, 2026, the SkyWater Board held a special meeting by video conference, together with representatives of Goldman Sachs and Foley, to review IonQ's final proposal, including the terms of the proposed Merger Agreement. Foley reviewed the SkyWater Board's fiduciary duties in connection with a potential sale transaction. Foley also reviewed with the SkyWater Board the interests SkyWater executive officers and directors may have in the Mergers that may be different from, or in addition to, those of SkyWater stockholders generally, as described in "-Interests of the Directors and Officers in the Mergers", a summary of which was provided to the SkyWater Board before the meeting. SkyWater management discussed the results of the reverse due diligence conducted by SkyWater management and advisors on IonQ. Also at this meeting, representatives of Goldman Sachs reviewed with the SkyWater Board certain transaction considerations and its financial analysis of the Merger Consideration and delivered to the SkyWater Board an oral opinion, and subsequently confirmed in a written opinion, dated January 25, 2026, that, as of January 25, 2026, and based upon and subject to the factors and assumptions set forth therein, the Merger Consideration to be paid to the holders (other than IonQ and its affiliates) of the outstanding shares of SkyWater common stock pursuant to the Merger Agreement is fair from a financial point of view to such holders, as discussed more fully in "-Opinion of SkyWater's Financial Advisor." Foley also presented an updated summary of the material terms of the Merger Agreement and Voting Agreement, which summary, along with copies of Merger Agreement and Voting Agreement, were circulated to the SkyWater Board in advance of the meeting. Foley also reviewed the resolutions that the SkyWater Board would consider at the meeting.

Having considered the various reasons to approve the Merger Agreement (see "-SkyWater Board's Recommendations and Its Reasons for the Transaction"), as well as certain countervailing factors noted therein, and taking into account the numerous discussions with SkyWater's management and financial and legal advisors, the SkyWater Board unanimously (a) declared that the Merger Agreement and the transactions contemplated thereby (including the Mergers), are fair to, and in the best interests of, SkyWater's stockholders, (b) approved and declared advisable the Merger Agreement and the transactions contemplated thereby (including the Mergers), (c) directed that the adoption of the Merger Agreement be submitted to a vote at a meeting of the SkyWater stockholders and (d) resolved (subject to certain exceptions set forth in the Merger Agreement) to recommend the adoption of the Merger Agreement and the transactions contemplated thereby (including the Mergers) by the SkyWater stockholders.

Later on January 25, 2026, (1) each of IonQ, SkyWater, Merger Subsidiary 1 and Merger Subsidiary 2 executed and delivered the Merger Agreement, and (2) each of IonQ, SkyWater, Merger Subsidiary 1, Merger Subsidiary 2, Mr. Unterseher and certain of Mr. Unterseher's affiliates executed and delivered the Voting Agreement.

On the morning of January 26, 2026, IonQ and SkyWater issued a press release announcing the execution of the Merger Agreement.

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IonQ's Rationale for the Transactions

IonQ believes that the merger with SkyWater will accelerate the company's technological roadmap toward scalable, real-world quantum advantage and will present IonQ with the opportunity to:

SkyWater Board's Recommendations and Its Reasons for the Transaction

By unanimous vote, the SkyWater Board, at a meeting held on January 25, 2026, (a) declared that the Merger Agreement and the transactions contemplated thereby (including the Mergers), are fair to, and in the best interests of, SkyWater's stockholders, (b) approved and declared advisable the Merger Agreement and the transactions contemplated thereby (including the Mergers), (c) directed that the adoption of the Merger Agreement be submitted to a vote at a meeting of the SkyWater stockholders and (d) resolved (subject to certain exceptions set forth in the Merger Agreement) to recommend the adoption of the Merger Agreement and the transactions contemplated thereby (including the Mergers) by the SkyWater stockholders. The SkyWater Board unanimously recommends that SkyWater stockholders vote "FOR" the merger proposal and "FOR" the adjournment proposal.

In reaching its determinations and recommendations, the SkyWater Board consulted with SkyWater's management and financial and legal advisors and considered a range of factors and scenarios. Factors that weighed in favor of the Mergers include:

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The SkyWater Board also considered a number of potentially negative factors in its deliberations concerning the Merger Agreement, the Mergers and the other transactions contemplated by the Merger Agreement, including the following (not in any relative order of importance):

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The foregoing discussion is not intended to be an exhaustive list of the information and considered by the SkyWater Board in its consideration of the Mergers but includes the material positive factors and material negative factors considered by the SkyWater Board in that regard. In view of the number and variety of factors, the amount of information considered and the complexity of these matters, SkyWater Board did not find it useful and did not attempt to quantify, rank or assign any relative or specific weights to the various factors that it considered. Individual members of the SkyWater Board may have given different weights to different factors. The SkyWater Board considered all these factors as a whole, and overall considered the factors to be favorable to, and to support, its unanimous determination.

In considering the SkyWater Board's recommendation to adopt the Merger Agreement, SkyWater's stockholders should be aware that the executive officers and directors of SkyWater have certain interests in the Mergers that may be different from, or in addition to, the interests of SkyWater's stockholders generally, as more fully described below under the section captioned section titled "-Interests of SkyWater Directors and Executive Officers in the Mergers." The SkyWater Board was aware of these interests and considered them when adopting the Merger Agreement and recommending that SkyWater stockholders vote to adopt the Merger Agreement.

Opinion of SkyWater's Financial Advisor

Goldman Sachs rendered its opinion to the SkyWater Board that, as of January 25, 2026, and based upon and subject to the factors and assumptions set forth therein, the Merger Consideration to be paid to the holders

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(other than IonQ and its affiliates) of the outstanding shares of SkyWater common stock pursuant to the Merger Agreement is fair from a financial point of view to such holders.

The full text of the written opinion of Goldman Sachs, dated January 25, 2026, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached as Annex C. Goldman Sachs provided advisory services and its opinion for the information and assistance of the SkyWater Board in connection with its consideration of the Transactions. Goldman Sachs' opinion is not a recommendation as to how any holder of SkyWater common stock should vote with respect to the Transactions or any other matter.

In connection with rendering the opinion described above and performing its related financial analyses, Goldman Sachs reviewed, among other things:

Goldman Sachs also held discussions with members of the senior managements of SkyWater and IonQ regarding their assessment of the strategic rationale for, and the potential benefits of, the Transactions and the past and current business operations, financial condition and future prospects of SkyWater and IonQ; reviewed the reported price and trading activity for SkyWater common stock and IonQ common stock; compared certain financial and stock market information for SkyWater and IonQ with similar information for certain other companies the securities of which are publicly traded; reviewed the financial terms of certain recent business combinations in the technology, media and telecommunications industry and in other industries; and performed such other studies and analyses, and considered such other factors, as it deemed appropriate.

For purposes of rendering this opinion, Goldman Sachs, with SkyWater's consent, relied upon and assumed the accuracy and completeness of all of the financial, legal, regulatory, tax, accounting and other information provided to, discussed with or reviewed by, it, without assuming any responsibility for independent verification thereof. In that regard, Goldman Sachs assumed with SkyWater's consent that the SkyWater management forecast was reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of SkyWater. Goldman Sachs did not make an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or other off-balance-sheet assets and liabilities) of SkyWater or IonQ or any of their respective subsidiaries and it was not furnished with any such evaluation or appraisal. Goldman Sachs assumed that all governmental, regulatory or other consents and approvals necessary for the consummation of the Transactions will be obtained without any adverse effect on SkyWater or IonQ or on the expected benefits of the Transactions in any way meaningful to its analysis. Goldman Sachs also assumed that the Transactions will be consummated on the terms set forth in the Merger Agreement, without the waiver or modification of any term or condition the effect of which would be in any way meaningful to its analysis.

Goldman Sachs' opinion does not address the underlying business decision of SkyWater to engage in the Transactions or the relative merits of the Transactions as compared to any strategic alternatives that may be

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available to SkyWater; nor does it address any legal, regulatory, tax or accounting matters. Goldman Sachs' opinion addresses only the fairness from a financial point of view, as of the date of the opinion, of the Merger Consideration to be paid to the holders (other than IonQ and its affiliates) of the outstanding shares of SkyWater common stock. Goldman Sachs' opinion does not express any view on, and does not address, any other term or aspect of the Merger Agreement or the Transactions or any term or aspect of any other agreement or instrument contemplated by the Merger Agreement or entered into or amended in connection with the Transactions, including any allocation of the Merger Consideration, the Equity Investment (as defined in the Merger Agreement), the fairness of the Transactions to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of SkyWater; nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of SkyWater, or class of such persons in connection with the Transactions, whether relative to the Merger Consideration to be paid to the holders (other than IonQ and its affiliates) of the outstanding shares of common stock of SkyWater in the Transactions or otherwise. Goldman Sachs' opinion is necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to Goldman Sachs as of, the date of its opinion and Goldman Sachs assumes no responsibility for updating, revising or reaffirming its opinion based on circumstances, developments or events occurring after the date of its opinion. In addition, Goldman Sachs does not express any opinion as to the prices at which shares of IonQ common stock or the shares of SkyWater common stock will trade at any time, as to the potential effects of volatility in the credit, financial and stock markets on SkyWater, IonQ or the Transactions, or as to the impact of the Transactions on the solvency or viability of SkyWater or IonQ or the ability of SkyWater or IonQ to pay their respective obligations when they come due. Goldman Sachs' opinion was approved by a fairness committee of Goldman Sachs.

The following is a summary of the material financial analyses delivered by Goldman Sachs to the SkyWater Board in connection with rendering the opinion described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Goldman Sachs, nor does the order of analyses described represent relative importance or weight given to those analyses by Goldman Sachs. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before January 23, 2026, the last trading day before the public announcement of the execution of the Merger Agreement and is not necessarily indicative of current market conditions.

Illustrative Discounted Cash Flow Analysis. Using the SkyWater management forecast, Goldman Sachs performed an illustrative discounted cash flow analysis on SkyWater to derive a range of illustrative present values per share of SkyWater common stock. Using the mid-year convention for discounting cash flows and discount rates ranging from 15.0% to 18.0%, reflecting estimates of SkyWater's weighted average cost of capital, Goldman Sachs discounted to present value, as of September 30, 2025, (i) estimates of unlevered free cash flow for SkyWater for the fiscal years 2025 through 2030 as reflected in the SkyWater management forecast and (ii) a range of illustrative terminal values for SkyWater, which were calculated by applying perpetuity growth rates ranging from 2.0% to 5.0%. The range of perpetuity growth rates was estimated by Goldman Sachs utilizing its professional judgment and experience, taking into account the SkyWater management forecast and market expectations regarding long-term real growth of gross domestic product and inflation. Goldman Sachs derived such discount rates by application of the Capital Asset Pricing Model, which requires certain company-specific inputs, including SkyWater's target capital structure weightings, the cost of long-term debt, after-tax yield on permanent excess cash, if any, future applicable marginal cash tax rate and a beta for SkyWater, as well as certain financial metrics for the United States financial markets generally.

Goldman Sachs derived ranges of illustrative enterprise values for SkyWater by adding the ranges of present values it derived above. Goldman Sachs then subtracted from the range of illustrative enterprise values it derived for SkyWater the amount of SkyWater's total debt and non-controlling interest and added the amount of SkyWater's cash and cash equivalents, in each case, as provided by and approved for Goldman Sachs' use by the management of SkyWater, to derive a range of illustrative equity values for SkyWater. Goldman Sachs then divided the range of illustrative equity values it derived by the number of fully diluted outstanding shares of SkyWater common stock, as provided by and approved for Goldman Sachs' use by the management of

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SkyWater, using the treasury stock method, to derive a range of illustrative present values per share ranging from $17.85 to $29.93.

Illustrative Present Value of Future Share Price Analysis. Using the SkyWater management forecast, Goldman Sachs performed an illustrative analysis of the implied present value of an illustrative future value per share of SkyWater common stock. For this analysis, Goldman Sachs first calculated the impliedenterprise value for SkyWater as of December 31 for each of the fiscal years 2025 through 2028, by applying a range multiples of illustrative enterprise value ("EV") to next twelve month ("NTM") Revenue ("EV/NTM Revenue") of 2.0x to 3.0x to estimates of SkyWater's NTM Revenue for each of the fiscal years 2025 through 2028. This illustrative range of EV/NTM Revenue multiple estimates was derived by Goldman Sachs utilizing its professional judgment and experience, taking into account current and historical EV/NTM Revenue multiples for SkyWater.

Goldman Sachs then subtracted the amount of SkyWater's total debt, non-controlling interest and added the amount of SkyWater's cash and cash equivalents for each of the fiscal years 2025 to 2028, each as provided by and approved for Goldman Sachs' use by the management of SkyWater, from the respective implied enterprise values in order to derive a range of illustrative equity values as of December 31 for SkyWater for each of the fiscal years 2025 to 2028. Goldman Sachs then divided these implied equity values by the projected year-end number of fully diluted outstanding shares of SkyWater common stock for each of the fiscal years 2025 to 2028, calculated using information provided by and approved for Goldman Sachs' use by the management of SkyWater, to derive a range of implied future values per share of SkyWater common stock (excluding dividends). Goldman Sachs then discounted these implied future equity values per share of SkyWater common stock to September 30, 2025, using an illustrative discount rate of 18.2%, reflecting an estimate of SkyWater's cost of equity. Goldman Sachs derived such discount rate by application of the Capital Asset Pricing Model, which requires certain company-specific inputs, including a beta for SkyWater, as well as certain financial metrics for the United States financial markets generally. This analysis resulted in a range of implied present values of $20.20 to $33.10 per share of SkyWater common stock.

Premia Paid Analysis. As reference, Goldman Sachs reviewed and analyzed, using publicly available information, the acquisition premia for transactions with 50-75% stock consideration announced from January 1, 2014, through January 23, 2026, involving a public company based in the United States as the target where the disclosed enterprise values for the transactions were greater than $1 billion. For the entire period, using publicly available information, Goldman Sachs calculated the median, 25th percentile and 75th percentile premiums of the price paid in the selected transactions relative to the target's closing share price 52-week high prior to announcement of the transaction. This analysis indicated a median premium of 8% across the period. This analysis also indicated a 25th percentile premium of (6)% and 75th percentile premium of 19% across the period. Using this analysis, Goldman Sachs applied a reference range of illustrative premiums of (6)% to 19% to the 52-week high per share of SkyWater common stock of $36.27 and calculated a range of implied equity values per share of SkyWater common stock of $34.09 to $43.16.

The preparation of a fairness opinion is a complex process and is not necessarily susceptible to partial analysis or summary description. Selecting portions of the analyses or of the summary set forth above, without considering the analyses as a whole, could create an incomplete view of the processes underlying Goldman Sachs' opinion. In arriving at its fairness determination, Goldman Sachs considered the results of all of its analyses and did not attribute any particular weight to any factor or analysis considered by it. Rather, Goldman Sachs made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses. No company or transaction used in the above analyses as a comparison is directly comparable to SkyWater or IonQ or the contemplated Transactions.

Goldman Sachs prepared these analyses for purposes of Goldman Sachs' providing its opinion to the SkyWater Board as to the fairness from a financial point of view of the Merger Consideration to be paid to the holders (other than IonQ and its affiliates) of the outstanding shares of SkyWater common stock. These analyses do not purport to be appraisals nor do they necessarily reflect the prices at which businesses or securities actually

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may be sold. Analyses based upon forecasts of future results are not necessarily indicative of actual future results, which may be significantly more or less favorable than suggested by these analyses. Because these analyses are inherently subject to uncertainty, being based upon numerous factors or events beyond the control of the parties or their respective advisors, none of SkyWater, IonQ, Goldman Sachs or any other person assumes responsibility if future results are materially different from those forecast.

The Merger Consideration was determined through arm's-length negotiations between SkyWater and IonQ and was approved by the SkyWater Board. Goldman Sachs provided advice to SkyWater during these negotiations. Goldman Sachs did not, however, recommend any specific amount of consideration to SkyWater or its board of directors or that any specific amount of consideration constituted the only appropriate consideration for the Transactions.

As described above, Goldman Sachs' opinion to the SkyWater Board was one of many factors taken into consideration by the SkyWater Board in making its determination to approve the Merger Agreement. The foregoing summary does not purport to be a complete description of the analyses performed by Goldman Sachs in connection with the fairness opinion and is qualified in its entirety by reference to the written opinion of Goldman Sachs attached as Annex C.

Goldman Sachs and its affiliates (collectively, "Goldman Sachs Affiliated Entities") are engaged in advisory, underwriting, lending and financing, principal investing, sales and trading, research, investment management and other financial and non-financial activities and services for various persons and entities. Goldman Sachs and its affiliates and employees, and funds or other entities they manage or in which they invest or have other economic interests or with which they co-invest, may at any time purchase, sell, hold or vote long or short positions and investments in securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments of SkyWater, IonQ, any of their respective affiliates and third parties, including affiliates of Mr. Loren A. Unterseher, a significant shareholder of SkyWater (the "Significant Shareholder"), and any of their respective affiliates and, as applicable, portfolio companies (collectively, "Related Entities") or any currency or commodity that may be involved in the Transactions contemplated by the Merger Agreement. Goldman Sachs acted as financial advisor to SkyWater in connection with, and participated in certain of the negotiations leading to, the Transactions. During the two-year period ended January 25, 2026, Goldman Sachs Investment Banking has not been engaged by SkyWater or its affiliates to provide financial advisory or underwriting services for which Goldman Sachs has recognized compensation. During the two-year period ended January 25, 2026, Goldman Sachs Investment Banking has not been engaged by IonQ or its affiliates to provide financial advisory or underwriting services for which Goldman Sachs has recognized compensation. As of January 25, 2026, Goldman Sachs Investment Banking was not mandated by IonQ and/or its Related Entities (excluding the Significant Shareholder and its other affiliates) to provide to any such person financial advisory and/or underwriting services. As of January 25, 2026, Goldman Sachs Investment Banking was not soliciting IonQ and/or its Related Entities (excluding the Significant Shareholder and its other affiliates) to work on financial advisory and/or underwriting matters for any such persons on which it has not been mandated. During the two-year period ended January 25, 2026, Goldman Sachs Investment Banking has not been engaged by the Significant Shareholder or its affiliates to provide financial advisory or underwriting services for which Goldman Sachs has recognized compensation. As of January 25, 2026, Goldman Sachs Investment Banking was not mandated by Loren A. Unterseher and/or his Related Entities (excluding SkyWater and its subsidiaries) to provide to any such person financial advisory and/or underwriting services. As of January 25, 2026, Goldman Sachs Investment Banking was not soliciting Loren A. Unterseher and/or his Related Entities (excluding SkyWater and its subsidiaries) to work on financial advisory and/or underwriting matters for any such persons on which it has not been mandated. Goldman Sachs may also in the future provide financial advisory and/or underwriting services to the Relevant Parties and their respective affiliates and/or as applicable, portfolio companies, for which Goldman Sachs Investment Banking may receive compensation.

As of January 25, 2026, Goldman Sachs Affiliated Entities had (i) no direct GS Principal Investment (as defined below) in SkyWater and/or its affiliates (excluding the Significant Shareholder and its other affiliates),

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(ii) no direct GS Principal Investment in IonQ and/or its affiliates (excluding the Significant Shareholder and its other affiliates) and (iii) no direct GS Principal Investments in the Significant Shareholder (but excluding IonQ, SkyWater or their other respective affiliates).As of January 25, 2026, funds managed by affiliates of Goldman Sachs Investment Banking were not co-invested with affiliates of the Significant Shareholder and were not invested in equity interests of funds managed by affiliates of the Significant Shareholder. Such funds managed by affiliates of Goldman Sachs Investment Banking may co-invest with, and invest in equity interests of, affiliates of the Significant Shareholder and/or funds managed thereby in the future.

On the public side of Goldman Sachs' informational wall (the "Public Side") and in the ordinary course of its various business activities, Goldman Sachs Affiliated Entities may also own equity securities in the Relevant Parties, and/or their respective affiliates arising from engaging in market making, trade execution, clearing, custody, margin lending and other similar financing transactions, securities lending, and related activities (including by acting as agent for third parties executing their transactions or as principal supplying liquidity to market participants, and any related hedging, other risk management or inventory management) (collectively, "Market Making Activities"), which positions change frequently. Regulatory, informational and operational barriers separate the Public Side from Goldman Sachs Investment Banking.

For purposes of this section of the proxy statement/prospectus, (x) Goldman Sachs relied on its books and records to (i) unless otherwise indicated, calculate all amounts and (ii) determine whether an entity is an affiliate, portfolio company, subsidiary or majority-owned subsidiary of another entity, and (y) the following terms have the definitions set forth below:

GS Principal Investments (including any associated commitments) are (i) direct balance sheet investments in equity interests or equity securities held by Goldman Sachs Affiliated Entities for its own account or (ii) direct investments in equity interests held by a fund managed by a Goldman Sachs Affiliated Entity which fund is primarily for the benefit of Goldman Sachs Affiliated Entities and/or its current and former employees and not third party clients. GS Principal Investments do not include equity interests arising from Market Making Activities, equity derivatives, convertible debt instruments, or warrants or equity kickers received in connection with senior secured loans, mezzanine loans, warehouse loans, preferred equity with a fixed rate of return or other similar types of financing transactions (which may also be subject to hedging or other risk-mitigating instruments). GS Principal Investments also do not include investments by funds managed by Goldman Sachs Affiliated Entities which funds are almost entirely for the benefit of third party clients ("GS Client Funds"), which funds can co-invest alongside, and/or make Investments in, the Relevant Parties or their respective Related Entities. As investment managers for GS Client Funds, Goldman Sachs Affiliated Entities are required to fulfill a fiduciary responsibility to GS Client Funds in making decisions to purchase, sell, hold or vote on, or take any other action with respect to, any financial instrument.

Related Entities are, as applicable, a person or entity's subsidiaries, affiliates, portfolio companies and/or funds managed thereby.

The SkyWater Board selected Goldman Sachs as its financial advisor because it is an internationally recognized investment banking firm that has substantial experience in transactions similar to the Transactions. Pursuant to a letter agreement dated December 11, 2025, SkyWater engaged Goldman Sachs to act as its financial advisor in connection with the contemplated Transactions. The engagement letter between SkyWater and Goldman Sachs provides for a transaction fee that is estimated, based on the information available as of the date of announcement, at approximately $33 million all of which is contingent upon consummation of the Transactions. In addition, SkyWater has agreed to reimburse Goldman Sachs for certain of its expenses, including attorneys' fees and disbursements, and to indemnify Goldman Sachs and related persons against various liabilities, including certain liabilities under the federal securities laws.

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SkyWater Unaudited Prospective Financial Information

SkyWater does not, as a matter of course, publicly disclose long-term consolidated forecasts as to future performance, earnings or other results because of, among other reasons, the uncertainty, unpredictability and subjectivity of the underlying assumptions and estimates underlying such forecasts. In connection with the SkyWater Board's consideration of the Transactions, SkyWater's management prepared certain unaudited financial projections regarding SkyWater's future performance for the fourth fiscal quarter of 2025 and the fiscal years 2026 through 2030 on a standalone basis without giving effect to the Mergers (the "SkyWater management forecast"), and provided the SkyWater management forecast to the SkyWater Board and to Goldman Sachs for its use in connection with its financial analyses (see the sections described above in this proxy statement/prospectus titled "The Mergers-Opinion of SkyWater's Financial Advisor" beginning on page [ ] of this proxy statement/prospectus). In addition, a summary of the SkyWater management forecast was made available to IonQ and the Merger Subsidiaries at IonQ's request in connection with their due diligence review of SkyWater. The SkyWater management forecast is based upon the internal financial model that SkyWater has historically used in connection with strategic planning.

The summaries of these projections are included in this proxy statement/prospectus to give SkyWater's stockholders access to non-public information that was provided to the SkyWater Board, Goldman Sachs, IonQ and the Merger Subsidiaries in the course of evaluating the proposed Mergers, and are not intended to influence your decision whether to vote in favor of the Merger Agreement proposal or any other proposal at the special meeting. The inclusion of this information should not be regarded as an indication that any of SkyWater or its advisors or other representatives or any other recipient of this information considered, or now considers, this information to be necessarily predictive of actual future performance or events, or that it should be construed as financial guidance, and such summary projections set forth below should not be relied on as such.

While presented with numeric specificity, the SkyWater management forecast reflects numerous estimates and assumptions that are inherently uncertain and may be beyond the control of SkyWater, including, among others, SkyWater's assumptions about SkyWater's goals and strategies; SkyWater's future business development, financial condition and results of operations; SkyWater's ability to operate its fabrication facilities at full capacity; SkyWater's ability to appropriately respond to changing technologies on a timely and cost-effective basis; SkyWater's customer relationships and its ability to retain and expand its customer relationships; the timing and amount of funding SkyWater's customers are able to secure for their purchase commitments; SkyWater's ability to accurately predict its future revenues for the purpose of appropriately budgeting and adjusting its expenses; SkyWater's expectations regarding dependence on its largest customers; SkyWater's ability to diversify and expand its customer base and develop relationships in new markets, and other matters described in the sections titled "Cautionary Note Regarding Forward-Looking Statements", "Where You Can Find More Information", and "Risk Factors", beginning on pages [ ], [ ] and [ ], respectively. The SkyWater management forecast reflects both assumptions as to certain business decisions that are subject to change and, in many respects, subjective judgment, and thus is susceptible to multiple interpretations and periodic revisions based on actual experience and business developments. SkyWater can give no assurance that the SkyWater management forecast and the underlying estimates and assumptions will be realized. In addition, since the SkyWater management forecast covers multiple years, such information by its nature becomes more speculative with each successive year. This information constitutes "forward-looking statements" and actual results may differ materially and adversely from those projected.

The SkyWater management forecast was not prepared with a view toward compliance with published guidelines of the SEC regarding projections or GAAP or the guidelines established by the American Institute of Certified Public Accountants for preparation or presentation of prospective financial information. The prospective financial information included in this document has been prepared by, and is the responsibility of, SkyWater's management. KPMG LLP has not audited, reviewed, examined, compiled nor applied agreed-upon procedures with respect to the accompanying prospective financial information and accordingly, KPMG LLP does not express an opinion or any other form of assurance with respect thereto. The reports of KPMG

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incorporated by reference into this proxy statement/prospectus relate to SkyWater's previously issued financial statements. They do not extend to the prospective financial information and should not be read to do so.

Adjusted EBITDA contained in the SkyWater management forecast and unlevered free cash flow derived therefrom, both as summarized below, are each a "non-GAAP financial measure," which is a financial performance measure that is not calculated in accordance with GAAP. The non-GAAP financial measures used in the SkyWater management forecast were relied upon by Goldman Sachs for purposes of its opinion and by the SkyWater Board in connection with its evaluation of the Mergers. The SEC rules which would otherwise require a reconciliation of a non-GAAP financial measure to a GAAP financial measure do not apply to non-GAAP financial measures included in disclosures relating to a proposed business combination such as the Mergers if the disclosure is included in a document such as this proxy statement/prospectus. In addition, reconciliations of non-GAAP financial measures were not relied upon by Goldman Sachs for purposes of its opinion or by the SkyWater Board in connection with its evaluation of the Mergers. Accordingly, SkyWater has not provided a reconciliation of the financial measures included in the SkyWater management forecast to the relevant GAAP financial measures. Non-GAAP financial measures should not be considered in isolation from, or as a substitute for, financial information presented in compliance with GAAP, and non-GAAP financial measures as used by SkyWater may not be comparable to similarly titled amounts used by other companies. Furthermore, there are limitations inherent in non-GAAP financial measures because they exclude charges and credits that are required to be included in a GAAP presentation. Accordingly, this non-GAAP financial measure should be considered together with, and not as an alternative to, financial measures prepared in accordance with GAAP.

Furthermore, the SkyWater management forecast does not take into account any circumstances or events occurring after the date it was prepared. SkyWater can give no assurance that, had the SkyWater management forecast been prepared as of the date of this proxy statement/prospectus, similar estimates and assumptions would have been used. Except as required by applicable securities laws, SkyWater does not intend to, and disclaims any obligation to, make publicly available any update or other revision to the SkyWater management forecast to reflect circumstances existing since its preparation or to reflect the occurrence of unanticipated events, even in the event that any or all of the underlying assumptions are shown to be in error or to reflect changes in general economic or industry conditions. The SkyWater management forecast does not take into account all the possible financial and other effects on SkyWater of the Mergers, the effect on SkyWater of any business or strategic decision or action that has been or will be taken as a result of the Merger Agreement having been executed or the effect of any business or strategic decisions or actions that would likely have been taken if the Merger Agreement had not been executed, but which were instead altered, accelerated, postponed or not taken in anticipation of the Mergers. Further, the SkyWater management forecast does not take into account the effect on SkyWater of any possible failure of the Mergers to occur. None of SkyWater or its affiliates, officers, directors, advisors or other representatives has made, makes or is authorized in the future to make any representation to any SkyWater stockholder or other person regarding SkyWater's ultimate performance compared to the information contained in the SkyWater management forecast or to the effect that the forecasted results will be achieved. The inclusion of the SkyWater management forecast herein should not be deemed an admission or representation by SkyWater or its advisors or any other person that it is viewed as material information of SkyWater, particularly in light of the inherent risks and uncertainties associated with such forecasts.

The SkyWater management forecast was prepared solely by SkyWater's management and reflects SkyWater management's view of SkyWater's standalone business and prospects as an independent company, without giving effect to the Mergers. IonQ did not participate in, and had no input into, the preparation of the SkyWater management forecast, and IonQ makes no representation with respect to the SkyWater management forecast or the assumptions on which it is based. The SkyWater management forecast is not reflective of IonQ's plans, expectations or views with respect to SkyWater's prospects or the management of its business following the Mergers. None of IonQ or any of its affiliates, officers, directors, advisors or other representatives has made or makes any representation to any SkyWater stockholder or any other person regarding SkyWater's ultimate performance compared to the information contained in the SkyWater management forecast or that forecasted results will be achieved.

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In light of the foregoing, and considering that the special meeting will be held several months after the SkyWater management forecast was prepared, as well as the uncertainties inherent in any forecasted information, SkyWater stockholders are cautioned not to place undue reliance on such information, and SkyWater urges all SkyWater stockholders to review SkyWater's most recent SEC filings for a description of SkyWater's reported financial results. See "Where You Can Find More Information" beginning on page [ ].

The following table summarizes the SkyWater management forecast as of December 2025 for the fourth fiscal quarter of 2025 and the fiscal years 2026 through 2030 ($ in millions):

Interests of Directors and Executive Officers of SkyWater in the Mergers

In considering the recommendation of the SkyWater Board that SkyWater stockholders approve the Transactions and vote in favor of the Merger Agreement proposal, SkyWater stockholders should be aware that the executive officers and directors of SkyWater have certain interests in the Mergers that are or may be different from, or in addition to, the interests of SkyWater's stockholders generally. The SkyWater Board was aware of these interests and considered them, among other matters, in evaluating and approving the Merger Agreement, and in making its recommendation that SkyWater stockholders adopt the Merger Agreement.

These interests are described in more detail below. The Mergers will be a "change in control" or a "change of control" for purposes of the SkyWater executive compensation plans and agreements described below.

For purposes of this disclosure, the executive officers of SkyWater are Thomas Sonderman, Chief Executive Officer; John Sakamoto, President and Chief Operating Officer; Steve Manko, Chief Financial Officer; and Christopher Hilberg, Chief Risk and Compliance Officer, General Counsel and Secretary. Although Mr. Hilberg is an executive officer of SkyWater, he is not a named executive officer and therefore a quantification of his transaction-related compensation is included within the narrative below and is not included in the section below titled "Quantification of Payments and Benefits to SkyWater's Named Executive Officers."

Certain Assumptions

Except as otherwise specifically noted, for purposes of quantifying the potential payments and benefits to Mr. Hilberg and our non-employee directors described in this section, the following assumptions were used:

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The amounts indicated below are estimates based on multiple assumptions (including the assumptions described above) that may or may not actually occur or be accurate on the relevant date, and do not reflect certain compensation actions that may occur before completion of the Transactions. Accordingly, the actual amounts received may differ from the estimates set forth below.

Treatment of SkyWater Equity Awards

SkyWater Stock Option Awards. At the Effective Time, each outstanding option to purchase shares of SkyWater common stock (each, a "SkyWater Option Award") that is outstanding, whether vested or unvested, will automatically be converted into an option to purchase a number of shares of IonQ common stock based on the Equity Award Exchange Ratio (as defined below) at an adjusted exercise price (as determined in accordance with the formula in the Merger Agreement), and otherwise will be subject to the same terms and conditions as applied immediately prior to the Effective Time.

SkyWater Employee RSU Awards. At the Effective Time, each award of restricted stock units relating to shares of SkyWater common stock held by a service provider other than a non-employee member of the SkyWater Board (each, a "SkyWater Employee RSU Award") that is outstanding, whether vested or unvested, will automatically be converted into a restricted stock unit award corresponding to a number of shares of IonQ common stock based on the Equity Award Exchange Ratio, and otherwise will be subject to the same terms and conditions (including any existing accelerated vesting provisions) as applied immediately prior to the Effective Time, with any related accrued but unpaid dividend equivalent rights carrying over and remaining payable in accordance with such preexisting terms.

SkyWater Director RSU Awards. Prior to the Effective Time, each award of restricted stock units relating to shares of SkyWater common stock held by a non-employee member of the SkyWater Board (each, a "SkyWater Director RSU Award") that is outstanding, whether vested or unvested, will automatically become fully vested and will be settled prior to the Effective Time, and any shares of SkyWater common stock issued thereunder will be treated in the same manner as all other shares of SkyWater common stock at the Effective Time.

Accelerated Vesting of Equity Awards Upon a Qualifying Termination. Each of the converted equity awards described above is required by the SkyWater 2021 Equity Incentive Plan (the "Equity Plan") to provide that, if the award holder's employment or service is terminated without "cause" (as defined in the Equity Plan) by IonQ or an affiliate thereof, or by the award holder for "good reason" (as defined in the Equity Plan) (if applicable), in either case, within 24 months (or, if provided in an award holder's award agreement, 12 months) following the Mergers, then, effective upon the date of such termination: (1) all of the award holder's outstanding stock options shall become fully vested and exercisable in full for a period of at least 90 days or such longer period provided by such award (but not beyond the award's expiration date), (2) all time-based vesting requirements of any of the award holder's outstanding awards will be deemed satisfied in full and (3) all performance-based vesting requirements of any of the award holder's outstanding awards for which the performance period has not yet ended will be deemed satisfied at the maximum level for such award. However, if the award holder has in effect an employment, retention, change of control, severance or similar agreement with SkyWater or any affiliate that discusses the effect of an award holder's termination of employment or service following the Mergers on the award holder's awards, then such agreement will control to the extent it provides better treatment than that described above.

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See "-Quantification of Payments and Benefits to SkyWater's Named Executive Officers" below for an estimate of the value of each SkyWater named executive officer's unvested SkyWater equity awards. Based on the assumptions described above under "-Certain Assumptions," the estimated value of unvested equity awards held by Mr. Hilberg (including the payment of accrued but unpaid dividend equivalent rights) is: unvested SkyWater Option Awards -$781,969 and unvested SkyWater Employee RSU Awards-$1,124,460. Based on the assumptions described above under "-Certain Assumptions," the estimated aggregate value of unvested SkyWater Director RSU Awards held by all eight non-employee directors of SkyWater (including the payment of accrued but unpaid dividend equivalent rights) is $3,001,450.

SkyWater ESPP. As soon as practicable, the SkyWater Board (or, if appropriate, any committee administering the ESPP) will adopt such resolutions and take such other actions as may be required so that:

Executive Severance Arrangements

Executive Severance and Change of Control Plan

SkyWater maintains the SkyWater Technology, Inc. Executive Severance and Change of Control Plan (the "Severance Plan"), which provides for specified payments and benefits to plan participants upon termination of employment as a result of severance eligible events. The participants in the Severance Plan include SkyWater's executive officers as well as other key employees of SkyWater. References to SkyWater in the following description of the Severance Plan will include IonQ as successor to SkyWater following the Mergers.

The severance multiple (corresponding to months of value) for plan benefits is 24 for individuals designated as Tier 1 participants and 12 for individuals designated as Tier 2 participants under the Severance Plan. The change of control severance multiple for plan benefits is 24 for individuals designated as Tier 1 participants and 18 for individuals designated as Tier 2 participants under the Severance Plan. Mr. Sonderman is a Tier 1 participant and each of Messrs. Sakamoto, Manko and Hilberg is a Tier 2 participant.

The Severance Plan provides for payments and benefits to participants as follows:

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A participant is entitled to benefits and payments under the Severance Plan (other than the Accrued Obligations) only upon the participant's timely execution of a release and the participant's compliance with the applicable restrictive covenants outlined in the Severance Plan. Payments and benefits under the Severance Plan are generally intended to be exempt from the provisions of Section 409A of the Internal Revenue Code. Any payments or benefits that constitute "nonqualified deferred compensation," that are provided as a result of a separation from service and that would otherwise be paid or provided during the first six months following the termination date to a participant who is a "specified employee" within the meaning of Section 409A of the Internal Revenue Code shall be accumulated and paid six months following the termination date.

Quantification

See the section titled "-Quantification of Payments and Benefits to SkyWater's Named Executive Officers" below for the estimated severance amounts for each named executive officer. Based on the assumptions described above under "-Certain Assumptions," the estimated cash severance that would be payable to Mr. Hilberg is $957,900 and the estimated cost of the COBRA continuation benefit for Mr. Hilberg is $45,676.

Retention Awards

SkyWater has, with the consent of IonQ, established a retention program providing for cash retention awards to certain key employees in an aggregate gross amount of approximately $13 million. The awards range in amount from 50% to 100% of the employee's base salary, depending on the employee's level and role. The awards will vest as follows:

See the section titled "-Quantification of Payments and Benefits to SkyWater's Named Executive Officers" below for the amount of the retention award that each of SkyWater's named executive officers is eligible to receive. The amount of Mr. Hilberg's retention award is $329,600.

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Indemnification and Insurance

The Merger Agreement provides certain continuation rights with respect to directors' and officers' liability insurance for the executive officers and non-employee directors of SkyWater intended to provide for continued coverage for at least six years following the Effective Time. This indemnification and insurance coverage is further described in the section titled "The Merger Agreement-Indemnification and Insurance of SkyWater Directors and Officers."

New Compensation Arrangements with IonQ

Any SkyWater executive officers and directors who become officers, directors or employees of IonQ or who otherwise are retained by IonQ to provide services may enter into new individualized compensation arrangements effective as of the Effective Time and may participate following the Effective Time in cash or equity incentive or other benefit plans maintained by IonQ, any of its affiliates or IonQ. As of the date of this proxy statement/prospectus, no compensation arrangements between such persons and IonQ and/or its affiliates have been established or discussed.

2026 Annual Bonus

Pursuant to the terms of the Merger Agreement, IonQ has agreed to honor the terms of SkyWater's annual cash bonus program for 2026 as in effect at the closing of the Mergers (the "2026 Bonus Program") and to determine the amount payable under the 2026 Bonus Program in a manner consistent with SkyWater's past practices, except that any bonus payable under the 2026 Bonus Program will be prorated for the portion of 2026 that has elapsed prior to the Effective Time.

See the section titled "-Quantification of Payments and Benefits to SkyWater's Named Executive Officers" below for the estimated amount of the prorated 2026 annual bonus that each of SkyWater's named executive officers would receive. Based on the assumptions described above under "-Certain Assumptions," and assuming solely for purposes of this disclosure that the actual level of performance is equal to 100% of the target level, the estimated prorated 2026 annual bonus payment that would be paid to Mr. Hilberg is $112,990.

Quantification of Payments and Benefits to SkyWater's Named Executive Officers

The information set forth below regarding the compensation of each of SkyWater's named executive officers that is based on or otherwise relates to the Mergers is provided in accordance with Item 402(t) of Regulation S-K.

Except as otherwise specifically noted, the disclosure below uses the following assumptions:

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The amounts indicated below are estimates based on multiple assumptions (including the assumptions described above) that may or may not actually occur or be accurate on the relevant date, and do not reflect certain compensation actions that may occur before completion of the Transactions. Accordingly, the actual amounts received by our named executive officers may differ from the estimates set forth below.

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SkyWater has represented in the Merger Agreement that, except as expressly provided in the Merger Agreement, the Transactions, either alone or in combination with another event, are not expected to result in any payment to any "disqualified individual" (within the meaning of Section 280G of the Code) that would constitute an "excess parachute payment" within the meaning of Section 280G(b)(1) of the Code. No named executive officer or non-employee director of SkyWater is entitled to a gross-up payment under Section 4999 of the Code in connection with the Mergers.

Share Ownership of Directors, Executive Officers and Certain Beneficial Owners of SkyWater

SkyWater's Directors and Executive Officers

The following table sets forth the number of shares and percentage of SkyWater common stock beneficially owned by SkyWater's named executive officers, each of its directors, and all of its executive officers and directors as a group as of March 5, 2026, the most recent practicable date for which such information was available. Except as otherwise indicated, the address for each of the named security holders is c/o SkyWater, Inc., 2401 East 86th Street, Bloomington, Minnesota 55425. None of the securities beneficially owned as set forth below is pledged as security.

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Certain Beneficial Owners of SkyWater common stock

The following table shows certain information regarding the beneficial ownership of SkyWater common stock as of March 5, 2026, the most recent practicable date for which such information was available, by each person who is known by SkyWater to beneficially own more than 5% of the outstanding SkyWater common stock.

Delinquent Section 16(a) Reports

Section 16(a) of the Exchange Act requires SkyWater's directors, executive officers and any owner of greater than 10% of SkyWater common stock to file reports with the SEC concerning their ownership of SkyWater common stock. Based solely upon information provided to SkyWater by individual directors, executive officers and owners of greater than 10% of SkyWater common stock, SkyWater believes that, during the fiscal year ended December 28, 2025, all of its directors, executive officers and owners of greater than 10%

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of SkyWater common stock timely complied with the Section 16(a) filing requirements, except that Forms 4s were filed late on behalf of Loren Unterseher, CMI Oxbow Partners, LLC and Oxbow Industries, LLC on May 23, 2025, September 23, 2025 and November 17, 2025.

Director and Officer Indemnification

Under the Merger Agreement, certain indemnification and insurance rights exist in favor of SkyWater and its subsidiaries' current and former directors and officers. For more information about these rights, see "The Mergers-Interests of Directors and Executive Officers of SkyWater in the Mergers-Indemnification and Insurance" beginning on page [ ].

Anticipated Accounting Treatment of the Mergers

IonQ and SkyWater prepare their respective financial statements in accordance with accounting principles generally accepted in the United States ("GAAP"). The mergers will be accounted for as a business combination, with IonQ as the accounting acquirer and SkyWater as the accounting acquiree, using the acquisition method of accounting in accordance with Accounting Standard Codification 805, Business Combinations, and, accordingly, will generally result in the recognition of SkyWater assets acquired and liabilities assumed at their estimated fair values as of the date of the completion of the mergers. The excess of the consideration transferred over the identifiable net assets acquired will be allocated to goodwill.

Regulatory Approvals Required for the Mergers

IonQ and SkyWater are not currently aware of any material governmental approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations or other confirmations that are required prior to the parties' completion of the Mergers other than those described below. If additional approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations and other confirmations are required to complete the Mergers, IonQ and SkyWater intend to seek such approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations and other confirmations.

Although IonQ and SkyWater believe that they will receive the required approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations and other confirmations to complete the Transactions, neither can give any assurance as to the timing of these approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations and other confirmations as to IonQ's and SkyWater's ultimate ability to obtain such approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations and other confirmations (or any additional approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations or other confirmations which may otherwise become necessary) or that such approvals, consents, registrations, permits, expirations or terminations of waiting periods, authorizations or other confirmations will be obtained on terms and subject to conditions satisfactory to IonQ and SkyWater. The receipt of the regulatory approvals (as described hereinafter) is a condition to the obligation of each of IonQ and SkyWater to complete the Mergers.

The Mergers are subject to the requirements of the HSR Act and the related rules and regulations, which provide that certain transactions may not be completed until notification and report forms have been furnished to the DOJ and the FTC and until certain waiting periods have been terminated or have expired. The HSR Act requires IonQ and SkyWater to observe a 30-calendar-day waiting period after the submission of their respective HSR notification and report forms before consummating their Mergers. The waiting period may be shortened if the reviewing agency grants "early termination" of the waiting period, or lengthened if the acquiring person (here IonQ) voluntarily withdraws and refiles to allow a second 30-calendar-day waiting period, or if the reviewing agency issues a request for additional information or documentary material (a "Second Request") prior to the expiration of the initial waiting period, the parties must observe a second 30-calendar-day waiting period, which begins to run only after each of the parties has substantially complied with the Second Request. It is also possible that IonQ and SkyWater could enter into a timing agreement with the FTC or DOJ that could affect the timing of the consummation of the Mergers.

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On February 20, 2026, IonQ and SkyWater each filed a notification and report form under the HSR Act with the DOJ and the FTC, which filings started the initial 30-calendar-day waiting period under the HSR Act.

Treatment of Existing Debt

In connection with the Transactions, SkyWater expects to fully repay and terminate its existing revolving credit facility with Siena Lending Group LLC and the other lenders party thereto, under which $195.5 million was outstanding as of December 28, 2025. Following the Transactions, IonQ expects to retain (i) SkyWater's lease agreement for the SkyWater Minnesota facility with Oxbow Realty, a consolidated variable interest entity of SkyWater, and the related $39 million loan agreement of Oxbow Realty used to finance the acquisition of the building and land of the SkyWater Minnesota facility and (ii) SkyWater's various financing arrangements for the purchase of manufacturing tools and other equipment.

Appraisal Rights

Record holders and beneficial owners of SkyWater common stock who comply with the procedures summarized below will be entitled to appraisal rights if the First Merger is completed. Under Section 262 of the DGCL, record holders and beneficial owners of shares of SkyWater common stock with respect to which appraisal rights are properly demanded and perfected and not withdrawn or lost are entitled to have such shares of SkyWater common stock appraised by the Delaware Court of Chancery. Shares of SkyWater common stock held by record holders and beneficial owners who properly exercise appraisal rights in accordance with Section 262 of the DGCL will not be converted into the right to receive the Merger Consideration, but instead will be canceled and represent the right to receive, in lieu of the Merger Consideration, a cash payment that is equal to the fair value of their shares of SkyWater common stock at the Effective Time (exclusive of any element of value arising from the accomplishment or expectation of the First Merger), as determined by the Delaware Court of Chancery, together with interest, if any as determined in accordance with Section 262 of the DGCL (the "appraisal payment"). The fair value of such shares of SkyWater common stock could be more than, less than or equal to the Merger Consideration. SkyWater is required to send a notice to that effect to each record holder, as of the record date, of SkyWater common stock not less than 20 days prior to the special meeting and include in the notice a copy of Section 262 of the DGCL or information directing the stockholders to a publicly available electronic resource at which Section 262 of the DGCL may be accessed without subscription or cost. This proxy statement/prospectus constitutes SkyWater's notice to the record holders of SkyWater common stock that appraisal rights are available in connection with the First Merger, and the full text of Section 262 of the DGCL may be accessed without subscription or cost at the following publicly available website: https://delcode.delaware.gov/title8/c001/sc09/index.html#262.

The following is intended as a brief summary of the material provisions of Section 262 of the DGCL, which sets forth the procedures for demanding statutory appraisal rights. This summary, however, is not a complete statement of the applicable requirements, and is qualified in its entirety by reference to Section 262 of the DGCL. All references in Section 262 of the DGCL to "stockholder" and in this summary to a "stockholder" or "holder" are to the record holder of shares of SkyWater common stock as to which appraisal rights are asserted and all such references to a "beneficial owner" are to a person who is the beneficial owner of SkyWater common stock held either in voting trust or by a nominee on behalf of such person. If you wish to consider exercising your appraisal rights, you should carefully review the text of Section 262 of the DGCL. Failure to comply timely and properly with the requirements of Section 262 of the DGCL may result in the loss of your appraisal rights under the DGCL. This notice does not constitute any legal or other advice, nor does it constitute a recommendation that holders or beneficial owners of SkyWater common stock exercise their appraisal rights under Section 262 of the DGCL. YOU ARE STRONGLY ENCOURAGED TO CONSULT A LEGAL ADVISOR BEFORE ATTEMPTING TO EXERCISE YOUR APPRAISAL RIGHTS.

Record holders and beneficial owners of SkyWater common stock who desire to exercise their appraisal rights must do all of the following: (i) not vote in favor of the adoption of the Merger Agreement, (ii) deliver in

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the manner set forth below a written demand for appraisal of such holder's or beneficial owner's shares of SkyWater common stock to the Secretary of SkyWater before the vote on the Merger Agreement proposal at the special meeting is taken, (iii) continuously hold of record or beneficially own, as applicable, such shares of SkyWater common stock from the date of making the demand through completion of the First Merger and (iv) otherwise comply with the requirements of Section 262 of the DGCL.

A demand for appraisal must be executed by or for the holder of record or beneficial owner, as applicable. The demand should set forth, fully and correctly, the person's identity. If shares are owned of record or beneficially owned by more than one person, as in a joint tenancy or tenancy in common, the demand must be executed by or on behalf of all such joint holders of record or beneficial owners. An authorized agent, including an agent of two or more joint holders of record or beneficial owners, may execute the demand for appraisal for a stockholder of record or beneficial owner; however, the agent must identify the record holder or holders or beneficial owner or owners, respectively, and expressly disclose that, in exercising the demand, the agent is acting as agent for the record holder or holders or beneficial owner or owners, as applicable.

As required by Section 262 of the DGCL, a demand for appraisal must be in writing and must reasonably inform SkyWater of the identity of the record holder or beneficial owner and of such holder's or beneficial owner's intention to seek appraisal of the holder's or beneficial owner's shares.

Record holders and beneficial owners of SkyWater common stock who elect to demand appraisal of their shares must mail or deliver their written demand to:

SkyWater Technology, Inc.

2401 East 86th Street

Bloomington, Minnesota

Attention: Christopher Hilberg

The written demand for appraisal should specify the stockholder's name and mailing address. In addition, in the case of a demand for appraisal of a beneficial owner, the demand must also (1) reasonably identify the holder of record of the shares for which the demand is made, (2) be accompanied by documentary evidence of the beneficial owner's ownership of stock (such as a brokerage or securities account statement containing such information or a letter from the broker or other record holder of such shares confirming such information) and a statement that such documentary evidence is a true and correct copy of what it purports to be and (3) provide an address at which such beneficial owner consents to receive notices given by the surviving corporation under Section 262 of the DGCL and the verified list required by subsection (f) of Section 262 of the DGCL (discussed further below). Whether made by a holder of record or a beneficial owner, the written demand must reasonably inform SkyWater that the SkyWater holder of record or beneficial owner intends thereby to demand an appraisal of his, her or its shares. The written demand must be received by SkyWater prior to the vote on the Merger Agreement proposal at the special meeting. Neither voting (in person or by proxy) against, abstaining from voting on or failing to vote on the Merger Agreement proposal will alone suffice to constitute a written demand for appraisal within the meaning of Section 262 of the DGCL. In addition, the holder or beneficial owner must not vote its shares of SkyWater common stock in favor of adoption of the Merger Agreement proposal. An executed proxy by a record holder that does not contain voting instructions will, unless revoked, be voted in favor of adoption of the Merger Agreement proposal and will cause the stockholder's right of appraisal to be lost. Therefore, a SkyWater stockholder who desires to exercise appraisal rights should either (x) refrain from executing and submitting the enclosed proxy card or (y) vote by proxy against the adoption of the Merger Agreement proposal or affirmatively register an abstention with respect thereto. In the case of a beneficial owner, brokers, banks and other nominees that hold shares of SkyWater common stock in "street name" for their customers do not have discretionary authority to vote on the Merger Agreement proposal without specific voting instructions from the beneficial owner on such proposal, but such brokers, banks or other nominees will vote such shares as instructed if the beneficial owner provides such instructions. If a beneficial owner of shares held in

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"street name" instructs such person's broker, bank or other nominee to vote such person's shares in favor of the Merger Agreement proposal, and does not revoke such instruction prior to the vote on the Merger Agreement proposal, then such shares will be voted in favor of the Merger Agreement proposal, and it will cause such beneficial owner to lose his, her or its right to appraisal and will nullify any previously delivered written demand for appraisal. Therefore, a beneficial owner who wishes to exercise appraisal rights must either not provide any instructions to such person's broker, bank or other nominee how to vote on the Merger Agreement proposal or must instruct such broker, bank or other nominee to vote against the Merger Agreement proposal or abstain from voting on such proposal.

Within 120 days after completion of the First Merger, either Merger Subsidiary 2 (as the surviving entity), or any holder or beneficial owner of shares of SkyWater common stock who has timely and properly demanded appraisal of such person's shares and who has complied with the requirements of Section 262 of the DGCL and is otherwise entitled to appraisal rights, may commence an appraisal proceeding by filing a petition in the Delaware Court of Chancery, with a copy served on Merger Subsidiary 2 (as the surviving entity) in the case of a petition filed by a stockholder or beneficial owner, demanding a determination of the fair value of the shares of all persons who have properly demanded appraisal. There is no present intent on the part of Merger Subsidiary 2 (as the surviving entity) to file an appraisal petition, and stockholders or beneficial owners seeking to exercise appraisal rights should not assume that Merger Subsidiary 2 (as the surviving entity) will file such a petition or that Merger Subsidiary 2 (as the surviving entity) will initiate any negotiations with respect to the fair value of such shares. Accordingly, record holders and beneficial owners of SkyWater common stock who desire to have their shares appraised should initiate any petitions necessary for the perfection of their appraisal rights within the time periods and in the manner prescribed in Section 262 of the DGCL. If no such petition is filed within that 120-day period, appraisal rights will be lost for such person.

Within 120 days after completion of the First Merger, any holder or beneficial owner of shares of SkyWater common stock who has complied with the applicable provisions of Section 262 of the DGCL will be entitled, upon written request, to receive from Merger Subsidiary 2 (as the surviving entity) a statement setting forth the aggregate number of shares of SkyWater common stock not voting in favor of the First Merger and with respect to which demands for appraisal were received by Merger Subsidiary 2 (as the surviving entity) and the number of holders or beneficial owners holding or owning such shares (provided that, in the case of a demand made by a beneficial owner in such person's name, the record holder of such shares shall not be considered a separate stockholder holding such shares for purposes of such aggregate number). Such statement must be mailed within 10 days after the written request therefor has been received by Merger Subsidiary 2 (as the surviving entity) or within 10 days after the expiration of the period for delivery of demands for appraisal, whichever is later.

If a petition for appraisal is duly filed by a holder or beneficial owner of SkyWater common stock and a copy of the petition is served upon Merger Subsidiary 2 (as the surviving entity), then Merger Subsidiary 2 (as the surviving entity) will be obligated, within 20 days after receiving service of a copy of the petition, to file with the Delaware Register in Chancery a duly verified list containing the names and addresses of all persons who have demanded an appraisal of their shares of SkyWater common stock and with whom agreements as to the value of their shares of SkyWater common stock have not been reached. Upon the filing of any such petition, the Delaware Court of Chancery may order the Delaware Register in Chancery to provide notice of the time and place fixed for the hearing on the petition be mailed to Merger Subsidiary 2 (as the surviving entity) and all of the persons shown on the verified list. The costs of these notices are borne by Merger Subsidiary 2 (as the surviving entity).

After notice to persons who have demanded appraisal, if such notice is ordered by the Delaware Court of Chancery, the Delaware Court of Chancery will conduct a hearing upon the petition and determine those persons who have complied with Section 262 of the DGCL and who have become entitled to appraisal rights. The Delaware Court of Chancery may require the persons who have demanded an appraisal for their shares and who hold stock represented by certificates to submit their certificates of stock to the Register in Chancery for notation thereon of the pendency of the appraisal proceedings; and if any person fails to comply with such direction, the

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Delaware Court of Chancery may dismiss the proceedings as to such person. Assuming shares of SkyWater common stock remain listed on a national securities exchange immediately before the First Merger (which we expect to be the case), the Delaware Court of Chancery must dismiss an appraisal proceeding as to all holders or beneficial owners of SkyWater common stock who assert appraisal rights unless (i) the total number of shares entitled to appraisal rights which have been pursued and perfected exceeds 1% of the outstanding shares of the class or series eligible for appraisal as measured in accordance with subsection (g) of Section 262 of the DGCL, or (ii) the value of the consideration provided in the First Merger (i.e., the Merger Consideration) for such total number of shares seeking appraisal exceeds $1.0 million, or (iii) the First Merger was approved pursuant to Section 253 or Section 267 of the DGCL (which, with respect to this clause (iii), we do not expect to be the case). Where proceedings are not dismissed, and after determining the persons entitled to an appraisal, the appraisal proceeding will be conducted, as to the shares of SkyWater common stock owned by such holders or beneficial owners of SkyWater common stock, in accordance with the rules of the Delaware Court of Chancery, including any rules specifically governing appraisal proceedings.

In determining fair value and the amount of the appraisal payment, if any, the Delaware Court of Chancery is required to take into account all relevant factors. In Weinberger v. UOP, Inc., the Supreme Court of Delaware discussed the factors that could be considered in determining fair value in an appraisal proceeding, stating that "proof of value by any techniques or methods which are generally considered acceptable in the financial community and otherwise admissible in court" should be considered and that "[f]air price obviously requires consideration of all relevant factors involving the value of a company." The Delaware Supreme Court has stated that in making this determination of fair value the court must consider market value, asset value, dividends, earnings prospects, the nature of the enterprise and any other facts which could be ascertained as of the date of the First Merger that throw any light on future prospects of the merged corporation. The Delaware Supreme Court has indicated that transaction price is one of the relevant factors the Court of Chancery may consider in determining "fair value" and that absent deficiencies in the sale process the transaction price should be given "considerable weight." Section 262 of the DGCL provides that fair value is to be determined "exclusive of any element of value arising from the accomplishment or expectation of the merger." In Cede & Co. v. Technicolor, Inc., the Delaware Supreme Court stated that such exclusion is a "narrow exclusion [that] does not encompass known elements of value," but which rather applies only to the speculative elements of value arising from such accomplishment or expectation. In Weinberger, the Delaware Supreme Court construed Section 262 of the DGCL to mean that "elements of future value, including the nature of the enterprise, which are known or susceptible of proof as of the date of the merger and not the product of speculation, may be considered."

Unless the Delaware Court of Chancery in its discretion determines otherwise for good cause shown, and except as provided in subsection (h) of Section 262 of the DGCL, interest from the effective date through the date of payment of the judgment will be compounded quarterly and will accrue at 5% over the Federal Reserve discount rate (including any surcharges) as established from time to time during the period between the effective date and the date of payment of the judgment.

At any time before the entry of judgment in the proceedings, Merger Subsidiary 2 (as the surviving entity) may pay to each person entitled to appraisal an amount in cash, in which case, interest will accrue thereafter as provided in Section 262 of the DGCL only upon the sum of (i) the difference, if any, between the amount so paid and the fair value of the shares as determined by the Delaware Court of Chancery, and (ii) interest theretofore accrued, unless paid at that time. When the appraisal payment is determined, the Delaware Court of Chancery will direct the payment of such value to the persons entitled thereto upon such terms and conditions as the Delaware Court of Chancery may order. The Delaware Court of Chancery's decree may be enforced as other decrees in such court may be enforced.

Record holders and beneficial owners of SkyWater common stock considering seeking appraisal should be aware that the fair value of their shares of SkyWater common stock could be more than, less than or equal to the Merger Consideration, and that opinions of investment banking firms as to the fairness from a financial point of view of the consideration payable in a transaction are not opinions as to fair value under Section 262 of the

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DGCL. Each of IonQ, Merger Subsidiary 2 (as the surviving entity) and SkyWater reserves the right to assert, in any appraisal proceeding, that for purposes of Section 262 of the DGCL, the "fair value" of a share of SkyWater common stock is less than the Merger Consideration.

Upon application by Merger Subsidiary 2 (as the surviving entity) or by any holder or beneficial owner of shares of SkyWater common stock entitled to participate in the appraisal proceeding, the Delaware Court of Chancery may, in its discretion, proceed to trial upon the appraisal prior to the final determination of the persons entitled to an appraisal. Any person whose name appears on the verified list filed by Merger Subsidiary 2 (as the surviving entity) pursuant to subsection (f) of Section 262 of the DGCL may participate fully in all proceedings until it is finally determined that such person is not entitled to appraisal rights under Section 262 of the DGCL. The Delaware Court of Chancery will direct the payment of the fair value of the shares, together with interest, if any, by Merger Subsidiary 2, as the surviving entity, to the persons entitled thereto. Payment shall be so made to each such person upon such terms and conditions as the Delaware Court of Chancery may order. The Delaware Court of Chancery's decree may be enforced as other decrees in such Court may be enforced.

The cost of the appraisal proceeding may be determined by the Delaware Court of Chancery and taxed upon the parties as the Delaware Court of Chancery deems equitable in the circumstances. However, costs do not include attorneys' and expert witness fees. The Delaware Court of Chancery may order that all or a portion of the expenses incurred by such holder or beneficial owner of SkyWater common stock in connection with the appraisal proceeding, including, without limitation, reasonable attorneys' fees and the fees and expenses of experts, be charged pro rata against the value of all shares entitled to appraisal. In the absence of such a determination of assessment, each party bears its own expenses.

From and after the date of completion of the First Merger, any holder or beneficial owner of SkyWater common stock who has duly demanded appraisal in compliance with Section 262 of the DGCL will not, after completion of the First Merger, be entitled to vote for any purpose any shares subject to such demand or to receive payment of dividends or other distributions on such shares, except for dividends or distributions payable to stockholders of record at a time prior to completion of the First Merger.

Within 10 days after the Effective Time, Merger Subsidiary 2 (as the surviving entity) must give notice of the date that the First Merger became effective to each holder of SkyWater common stock who has properly filed a written demand for appraisal, who did not vote in favor of the proposal to adopt the Merger Agreement and who has otherwise complied with Section 262 of the DGCL and any beneficial owner who has demanded appraisal in such person's name pursuant to Section 262 of the DGCL. At any time within 60 days after the Effective Time, any holder or beneficial owner of SkyWater common stock who has demanded appraisal and who has not commenced an appraisal proceeding or joined that proceeding as a named party will have the right to withdraw such person's demand for appraisal and to accept the Merger Consideration to which the person is entitled pursuant to the First Merger. After this period, a holder or beneficial owner of SkyWater common stock may withdraw such person's demand for appraisal only with the written approval of Merger Subsidiary 2 (as the surviving entity). Notwithstanding the foregoing, no petition timely filed in the Delaware Court of Chancery demanding appraisal will be dismissed as to any person without the approval of the Delaware Court of Chancery, and that approval may be conditioned upon such terms as the Delaware Court of Chancery deems just. However, the preceding sentence will not affect the right of any record holder or beneficial owner of SkyWater common stock who has not commenced an appraisal proceeding or joined the proceeding as a named party to withdraw such person's demand for appraisal and to accept the terms offered upon the merger within 60 days after completion of the First Merger as summarized in the second sentence of this paragraph.

If no petition for appraisal is filed with the Delaware Court of Chancery within 120 days after completion of the First Merger, appraisal will cease and all record holders and beneficial owners of SkyWater common stock will be entitled only to receive the Merger Consideration as provided for in the Merger Agreement.

The foregoing is only a brief summary of Section 262 of the DGCL that sets forth the procedures for demanding statutory appraisal rights. This summary, however, is not a complete statement of all applicable

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requirements and is qualified in its entirety by reference to Section 262 of the DGCL, a copy of which may be accessed without subscription or cost at the following publicly available website: https://delcode.delaware.gov/title8/c001/sc09/index.html#262.

Failure to comply with all the procedures set forth in Section 262 of the DGCL may result in the loss of a holder's or beneficial owner's statutory appraisal rights. Consequently, if you wish to exercise your appraisal rights, you are strongly urged to consult a legal advisor before attempting to exercise your appraisal rights.

NYSE Listing of IonQ Common Stock, Delisting and Deregistration of SkyWater Common Stock

Prior to the completion of the Mergers, IonQ has agreed to take all necessary action to cause the shares of IonQ common stock to be issued in connection with the Mergers to be approved for listing on the NYSE subject to official notice of issuance. The listing on the NYSE of the shares of IonQ common stock to be issued in connection with the Mergers is also a condition to completion of the Mergers.

Prior to the Effective Time, SkyWater will cooperate with IonQ and use its reasonable best efforts to take, or cause to be taken, all actions and do, or cause to be done, all things reasonably necessary, proper or advisable on its part pursuant to applicable law and the rules and regulations of the Nasdaq to cause (a) the delisting of SkyWater common stock from Nasdaq as promptly as practicable after the Effective Time and (b) the deregistration of SkyWater common stock pursuant to the Exchange Act as promptly as practicable after such delisting. If the Mergers are completed, SkyWater common stock will cease to be listed on Nasdaq and SkyWater common stock will be deregistered under the Exchange Act, after which SkyWater will no longer be required under SEC rules and regulations to file periodic reports with the SEC in respect of SkyWater common stock.

Material U.S. Federal Income Tax Consequences

The following is a general discussion of the material U.S. federal income tax consequences of the Mergers to U.S. Holders (as defined below) of SkyWater common stock that exchange their SkyWater common stock for IonQ common stock in the Mergers.

This discussion is based upon the Code, its legislative history, U.S. Treasury regulations promulgated under the Code and judicial and administrative rulings and decisions, all as in effect on the date of this proxy statement/prospectus. These authorities may change, possibly retroactively, or be subject to differing interpretations, and any such change or differing interpretation could affect the accuracy of the statements and conclusions set forth in this discussion.

This discussion addresses only those U.S. Holders (as defined below) of SkyWater common stock that hold their SkyWater common stock as a "capital asset" within the meaning of Section 1221 of the Code (generally, property held for investment). This discussion is not a complete description of all of the U.S. federal income tax consequences of the Mergers and, in particular, does not address any tax consequences arising under the Medicare contribution tax on net investment income or the Foreign Account Tax Compliance Act of 2010 (including the U.S. Treasury regulations promulgated thereunder and intergovernmental agreements entered into pursuant thereto or in connection therewith), nor does it address any tax consequences arising under the laws of any state, local or non-U.S. jurisdiction, any U.S. federal estate, gift, generation skipping or alternative minimum tax considerations, or under any U.S. federal laws other than those pertaining to the income tax (including in connection with the ownership and disposition of any IonQ common stock received by a U.S. Holder in the Mergers). Further, this discussion does not address all aspects of U.S. federal income taxation that may be relevant to you in light of your individual circumstances or that may be applicable to you if you are subject to special treatment under the U.S. federal income tax laws, including if you are:

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For purposes of this discussion, a "U.S. Holder" means a beneficial owner of shares of SkyWater common stock that is, for U.S. federal income tax purposes either:

Beneficial owners of SkyWater common stock that are not U.S. Holders should consult their own tax advisors as to the U.S. federal income tax consequences of the Mergers.

If an entity or an arrangement treated as a partnership for U.S. federal income tax purposes holds shares of SkyWater common stock, the U.S. federal income tax consequences to a partner in such partnership generally will depend on the status of the partner and the activities of the partner and partnership. Any entity or

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arrangement treated as a partnership for U.S. federal income tax purposes that holds shares of SkyWater common stock, and any persons that, for U.S. federal income tax purposes, are treated as partners in such partnership, should consult their own tax advisors with respect to the tax consequences of the Mergers in their specific circumstances.

This discussion is not tax advice and does not purport to be a complete analysis or discussion of all U.S. federal income tax considerations relating to the Mergers. The tax consequences of the Mergers may be complex and will depend on your specific situation and factors not within IonQ's or SkyWater's control.

All holders of SkyWater common stock should consult their own tax advisors as to the specific tax consequences to them of the Transactions, including the applicability and effect of the alternative minimum tax and any U.S. state, local, non-U.S. and other tax laws.

In General

The U.S. federal income tax consequences of the Mergers will depend primarily upon whether the Mergers, taken together, qualify as a "reorganization" under Section 368(a) of the Code. IonQ and SkyWater intend that, for U.S. federal income tax purposes, the First Merger, taken together with the Second Merger, will qualify as a "reorganization" within the meaning of Section 368(a) of the Code (the "Intended Tax Treatment"). However, whether or not the Mergers will qualify for the Intended Tax Treatment depends on facts that may not be known until after the second to last trading day prior to the Closing Date.

The Intended Tax Treatment requires, among other requirements, that the value of the shares of IonQ common stock issued to holders of SkyWater common stock in the Mergers represents at least a certain minimum percentage of the total consideration paid to holders of SkyWater common stock in the Mergers. While there is no specific guidance as to precisely what minimum percentage is necessary to satisfy this requirement, it would be satisfied if the value of IonQ common stock received in the Mergers (measured by taking the Average of the Daily Volume Weighted Average Prices (as defined in the Merger Agreement) of SkyWater common stock on the ten consecutive trading days ending on and including the second to last trading day prior to the Closing Date) represents at least 40% of the total value of the merger consideration. Because this test is based on the value of IonQ common stock as of an average value of the shares on the days preceding the completion of the Mergers, a substantial decline in the value of the IonQ common stock from its value as of the execution of the Merger Agreement on January 25, 2026 could cause this requirement to not be met if the value of all IonQ common stock received by holders of SkyWater common stock in the Mergers represents less than 40% of the total value of the merger consideration received by holders of SkyWater common stock in the Mergers, i.e., as a result in a decline in the value of SkyWater common stock (for a description of how the Exchange Ratio operates across various IonQ Trading Prices, including the collar floor of $37.99 and ceiling of $60.13, see "The Merger Agreement-Merger Consideration" beginning on page [ ]). Accordingly, no assurance can be given that the Mergers will qualify for the Intended Tax Treatment.

IonQ and SkyWater have covenanted in the Merger Agreement to not take any action that would prevent or impede, or could reasonably be expected to prevent or impede, the Mergers from qualifying for the Intended Tax Treatment. Any opinion delivered in connection with this summary of the Material U.S. Federal Income Tax Consequences is effective as of the date of this registration statement, and there can be no assurance that it will continue to remain valid at closing. The closing of the Mergers is not conditioned on the continuing validity of any opinion delivered in connection with this registration statement, nor on the receipt of any other opinion of counsel as to the qualification of the Mergers for the Intended Tax Treatment.

Neither IonQ nor SkyWater intends to request a ruling from the IRS regarding the U.S. federal income tax consequences of the Mergers. Accordingly, even if an opinion of counsel concludes that the Mergers qualify for the Intended Tax Treatment, no assurance can be given that the IRS will not challenge that conclusion or that a court would not sustain such a challenge. If the IRS successfully challenges the Intended Tax Treatment, U.S. Holders will be treated as if they sold their SkyWater common stock in a fully taxable transaction (as described below under "-Tax Consequences if the Mergers Fail to Qualify for the Intended Tax Treatment").

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Tax Consequences if the Mergers Qualify for the Intended Tax Treatment

Assuming that the Mergers qualify for the Intended Tax Treatment, the U.S. federal income tax consequences of the Mergers to U.S. Holders of SkyWater common stock are as follows:

If a U.S. Holder acquired different blocks of SkyWater common stock at different times or at different prices, such U.S. Holder's basis and holding period in its shares of SkyWater common stock may be determined separately with reference to each block of SkyWater common stock. Any such U.S. Holder should consult its tax advisor regarding the determination of the tax basis and/or holding periods of the particular shares of IonQ common stock received in the Mergers.

Subject to the discussion below under "-Possible dividend treatment," any gain or loss recognized by a U.S. Holder would generally be long-term capital gain or loss if the U.S. Holder's holding period in a particular block of SkyWater common stock exceeds one year as of the effective date of the Mergers. Long-term capital gain of certain non-corporate U.S. Holders (including individuals) is currently eligible for preferential U.S. federal income tax rates.

Possible dividend treatment. In some cases, the recognized gain discussed above could be treated as a dividend for U.S. federal income tax purposes. Because the possibility of dividend treatment can depend upon various factors, including the particular circumstances of a U.S. Holder and the application of certain constructive ownership rules, U.S. Holders should consult their tax advisors regarding the potential tax consequences of the Mergers and the receipt of the merger consideration to them.

Receipt of cash in lieu of fractional shares. A U.S. Holder who receives cash instead of a fractional share of IonQ common stock generally will be treated as having received the fractional share pursuant to the Mergers and then as having sold to IonQ that fractional share of IonQ common stock for cash. As a result, a U.S. Holder generally will recognize gain or loss equal to the difference between the amount of cash received and the tax basis allocated to such fractional share of IonQ common stock. Gain or loss recognized with respect to cash received in lieu of a fractional share of IonQ common stock will generally be capital gain or loss, and will be long-term capital gain or loss if, as of the Effective Time, the holding period for such shares is greater than one year. The deductibility of such capital losses is subject to limitations.

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Whether the requirements for the Mergers to qualify for the Intended Tax Treatment are met may not be known at the time of the Special Meeting. However, SkyWater will not resolicit stockholder votes in the event that the Mergers fail to qualify for the Intended Tax Treatment.

Tax Consequences if the Mergers Fail to Qualify for the Intended Tax Treatment

If any requirement for the Mergers to qualify for the Intended Tax Treatment is not satisfied, a U.S. Holder whose shares of SkyWater common stock are converted into the right to receive the Merger Consideration generally will recognize capital gain or loss in an amount equal to the difference between (i) the fair market value of the shares of IonQ common stock and the amount of cash consideration received in the Mergers (including cash received in lieu of fractional shares of IonQ common stock) and (ii) the U.S. Holder's tax basis in the SkyWater common stock surrendered. Additionally, a U.S. Holder's holding period in shares of IonQ common stock received in the First Merger would begin on the day following the Mergers.

If a U.S. Holder acquired different blocks of SkyWater common stock at different times or different prices, any gain or loss will generally be determined separately with respect to each block of SkyWater common stock, and such U.S. Holder's tax basis and holding period in its shares of IonQ common stock may be determined with reference to each block of SkyWater common stock. Any such U.S. Holders should consult their own tax advisors regarding the manner in which cash and IonQ common stock received in the exchange should be allocated among different blocks of SkyWater common stock and with respect to identifying the tax bases or holding periods of the particular shares of IonQ common stock received in the Mergers.

Any gain or loss recognized by a U.S. Holder would generally be long-term capital gain or loss if the U.S. Holder's holding period in a particular block of SkyWater common stock exceeds one year as of the effective date of the Mergers. Long-term capital gain of certain non-corporate U.S. Holders (including individuals) is currently eligible for preferential U.S. federal income tax rates. The deductibility of capital losses is subject to limitations.

Information Reporting and Backup Withholding

The receipt of the merger consideration in exchange for SkyWater common stock pursuant to the Mergers may be subject, under certain circumstances, to information reporting and backup withholding at a rate of 24%. To prevent backup withholding, U.S. Holders should timely furnish a properly completed IRS Form W-9 or successor form (or appropriate substitute) included in the letter of transmittal such U.S. Holder will receive certifying such U.S. Holder is a "United States person" (within the meaning of the Code), that the taxpayer identification number provided is correct and that such U.S. Holder is not subject to backup withholding and otherwise complying with all the applicable requirements of the backup withholding rules.

Any amounts withheld under the backup withholding rules are not an additional tax and will generally be allowed as a refund or credit against a U.S. Holder's U.S. federal income tax liability, if any, provided that such U.S. Holder timely furnishes the required information to the IRS. The IRS may impose a penalty upon a U.S. Holder that fails to provide the correct taxpayer identification number.

The preceding discussion is intended only as a general discussion of material U.S. federal income tax consequences of the Mergers. The preceding discussion is not a complete analysis or discussion of all potential tax effects that may be important to you. You are strongly encouraged to consult your own tax advisors as to the specific tax consequences of the Mergers including tax return reporting requirements, the applicability and effect of federal, state, local and other tax laws and the effect of any proposed changes in the tax laws.

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THE MERGER AGREEMENT

Explanatory Note Regarding the Merger Agreement

This section of this proxy statement/prospectus describes the material provisions of the Merger Agreement, but does not describe all of the terms of the Merger Agreement and may not contain all of the information about the Merger Agreement that is important to you. The following summary is qualified by reference to the complete text of the Merger Agreement, which is attached as Annex A to this proxy statement/prospectus and incorporated by reference into this proxy statement/prospectus. The rights and obligations of IonQ, Merger Subsidiary 1, Merger Subsidiary 2 and SkyWater are governed by the express terms and conditions of the Merger Agreement and not by this summary or any of the other information contained in this proxy statement/prospectus. You are urged to read the full text of the Merger Agreement because it is the legal document that governs the Mergers.

The Merger Agreement contains representations, warranties and covenants by each of the parties to the Merger Agreement, which were made only for purposes of the Merger Agreement, as of specified dates. The representations, warranties and covenants in the Merger Agreement were made solely for the benefit of the parties to the Merger Agreement; may be subject to limitations agreed upon by the contracting parties, including being qualified by confidential disclosures made for the purposes of allocating contractual risk between the parties to the Merger Agreement instead of establishing these matters as facts; and may be subject to standards of materiality applicable to the contracting parties that differ from those applicable to investors. Investors should not rely on representations, warranties and covenants or any descriptions thereof as characterizations of the actual state of facts or condition of IonQ, Merger Subsidiary 1, Merger Subsidiary 2 and SkyWater or any of their respective subsidiaries or affiliates. Moreover, information concerning the subject matter of the representations, warranties and covenants contained in the Merger Agreement or any other agreement between the parties to the applicable agreement may change after the date of each such agreement, which subsequent information may or may not be fully reflected in IonQ's or SkyWater's public disclosures or the public disclosures of any of their respective subsidiaries or affiliates. Each such agreement should not be read alone, but should instead be read in conjunction with the other information regarding the respective agreement, the Transactions, IonQ, SkyWater and their respective affiliates and businesses, which is contained in, or incorporated by reference to, this proxy statement/prospectus, as well as in the Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and other filings that each of IonQ and SkyWater has made or will make with the SEC. See the section titled, "Where You Can Find More Information" beginning on page [ ].

Structure of the Mergers

The Merger Agreement provides that, on the terms and subject to the conditions set forth in the Merger Agreement, and in accordance with the DGCL, the parties will complete two mergers. In the First Merger, Merger Subsidiary 1 will merge with and into SkyWater, with SkyWater continuing as the surviving corporation in the First Merger. Immediately following the Effective Time, and as part of the same plan, the surviving corporation of the First Merger will merge with and into Merger Subsidiary 2, with Merger Subsidiary 2 surviving as the Surviving Company of the Second Merger. Following the Second Merger, the Surviving Company will be a wholly-owned direct subsidiary of IonQ. The two-step structure is intended, among other things, to facilitate the qualification of the Mergers, taken together, as a "reorganization" within the meaning of Section 368(a) of the Code.

At the effective time of the Second Merger, the governing documents of SkyWater will be amended and restated in its entirety as set forth in the limited liability agreement of Merger Subsidiary 2, as in effect immediately prior to the Effective Time, except that all references therein to Merger Subsidiary 2 will be automatically amended and will become references to SkyWater. The directors of Merger Subsidiary 2 immediately prior to the Effective Time will be the initial directors of the Surviving Company, each to hold office in accordance with the governing documents of the Surviving Company, and the officers of Merger Subsidiary 2 immediately prior to the Effective Time will be the initial officers of the Surviving Company, in

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each case, until their respective successors are duly elected or appointed and qualified or until their earlier death, resignation or removal.

Timing of Closing

The closing of the Mergers (the "Closing") will take place on the third business day following the day of fulfillment or waiver in accordance with the Merger Agreement by the parties to the Merger Agreement having the benefit of the applicable condition (to the extent permitted by applicable law) of the conditions described under the heading "-Conditions to Completion of the Mergers" beginning on page [  ] (other than those conditions that by their nature are to be fulfilled at the Closing, but subject to the fulfillment or waiver of such conditions), or at such other place, date and time as IonQ and SkyWater may agree in writing. The date on which the Closing actually occurs is referred to in this proxy statement/prospectus as the "Closing Date."

Merger Consideration

Effects of the Mergers

At the Effective Time, by virtue of the First Merger and without any action on the part of IonQ, Merger Subsidiary 1, SkyWater or the holders of any of the following securities:

The First Merger shall become effective at such time as the certificate of merger with respect to the First Merger with the Secretary of State of the State of Delaware (the "First Certificate of Merger") is duly filed with the Secretary of State of the State of Delaware or at such later time as IonQ and the SkyWater may agree and is specified in the First Certificate of Merger (which is the "Effective Time"). The Second Merger shall become effective upon the filing of the certificate of merger with respect to the Second Merger with the Secretary of State of the State of Delaware ( the "Second Certificate of Merger") with the Secretary of State of the State of Delaware, or at such later time as IonQ and the SkyWater may agree and is specified in the Second Certificate of Merger (such date and time being hereinafter referred to as the "Second Effective Time"). The Effective Time shall, in all events, precede the Second Effective Time.

The "Exchange Ratio" is the following (in each case, rounded to four decimals): (A) if the IonQ Trading Price is an amount equal to or less than $37.99, then the Exchange Ratio shall be 0.5265; (B) if the IonQ Trading Price is an amount greater than $37.99 but less than $60.13, then the Exchange Ratio shall be equal to the

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quotient obtained by dividing $20 by the IonQ Trading Price; and (C) if the IonQ Trading Price is an amount greater than or equal to $60.13, then the Exchange Ratio shall be 0.3326.

The table above is for illustrative purposes only and does not represent the actual IonQ Trading Price or Exchange Ratio at the time of the Mergers.

The "IonQ Trading Price" is the volume-weighted average price (VWAP), rounded to four decimal places, of IonQ common stock on all exchanges as reported by Bloomberg L.P. on the VWAP function for the ticker "[IonQ, Inc. US Equity]" for the 20 full consecutive trading days prior to, but not including, the third business day prior to the Closing Date, calculated from market open (9:30 a.m. Eastern Time) on the first day of the measurement period to market close on the last day of the measurement period (4:00 p.m. Eastern Time).

No election will be made available to any holder of SkyWater common stock with respect to the form of consideration to be received by such holder in the First Merger. As a result, each holder of SkyWater common stock will receive both the Per Share Cash Consideration and the Per Share Stock Consideration for each share of SkyWater common stock held by such holder (other than Cancelled Shares and Appraisal Shares).

From and after the Effective Time, the First Surviving Corporation will possess all rights, privileges, powers and franchises of each of SkyWater and Merger Subsidiary 1 and will be subject to all of their restrictions, disabilities and duties, as provided by the DGCL.

At the Second Effective Time, immediately following the Effective Time and as part of the same plan, each issued and outstanding share of common stock of the First Surviving Corporation immediately prior to the Second Effective Time will be canceled and retired without any consideration being delivered in exchange, and each limited liability company interest of Merger Subsidiary 2 immediately prior to the Second Effective Time will remain outstanding as an LLC interest of the Surviving Company.

Appraisal Rights

Notwithstanding anything in the Merger Agreement to the contrary, Appraisal Shares will not be converted into, or represent the right to receive, the Merger Consideration under the heading "-Merger Consideration- Effects of the Mergers," but instead will be canceled and will represent only the right to receive such amounts as may be determined to be due with respect to those shares in accordance with Section 262 of the DGCL. If any such person fails to perfect or otherwise waives, withdraws or loses the right to appraisal under Section 262 of the DGCL, or if a court of competent jurisdiction determines that such person is not entitled to the relief provided by Section 262 of the DGCL, then that person's Appraisal Shares will thereupon be deemed, as of the Effective Time, to have been converted into, and to represent only the right to receive, the Merger Consideration, without interest thereon.

SkyWater will give prompt notice to IonQ of any demands received by SkyWater for appraisal of any shares of SkyWater common stock, any written withdrawal or purported withdrawal of any such demand, and any other

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demand, notice or instrument delivered to SkyWater prior to the Effective Time pursuant to the DGCL relating to such appraisal demands. IonQ will have the right to participate in and direct all negotiations and any litigation, suit, action or other proceeding to the extent related to those appraisal demands, and SkyWater will consider in good faith any comments or suggestions proposed by IonQ with respect thereto. Prior to the Effective Time, SkyWater will not, without the prior written consent of IonQ, make any payment with respect to, offer to settle or settle, or approve the withdrawal of, any appraisal demands, or agree to do any of the foregoing,

Deposit of Merger Consideration

The SkyWater book-entry shares will be exchanged in accordance with the procedures described below.

Prior to the Effective Time, IonQ will appoint a bank, trust company, nationally recognized stockholder services provider, or other person reasonably acceptable to SkyWater to act as exchange agent (the "Exchange Agent") for the purpose of exchanging certificates and book-entry shares and paying the aggregate Merger Consideration under the agreement. IonQ will make available to the Exchange Agent, as needed, evidence of book-entry shares representing IonQ common stock issuable in respect of SkyWater common stock, together with the cash necessary to make the payments described under the heading "-Merger Consideration-Effects of the Mergers." The IonQ common stock and cash so deposited are referred to as the "Exchange Fund."

Exchange Procedures

Promptly after the Effective Time, IonQ will send, or cause the Exchange Agent to send, to each holder of record, as of the Effective Time, of SkyWater common stock: (i) a letter of transmittal (which will specify that delivery will be effected, and risk of loss and title will pass, only upon proper delivery of certificates to the Exchange Agent) and (ii) instructions for use in effecting the surrender of certificates for payment of the Merger Consideration therefor, in such form as IonQ and SkyWater may reasonably agree; exchanges of book-entry shares will be effected in accordance with IonQ's customary book-entry procedures.

Each former SkyWater holder who surrenders to the Exchange Agent certificate(s) or book-entry shares, together with a duly completed letter of transmittal and such other documents as may be required by the instructions thereto, will be entitled to receive in exchange therefor: (A) one or more shares of IonQ common stock (in uncertificated book-entry form) representing, in the aggregate, the whole number of shares of IonQ common stock, if any, into which such holder's SkyWater shares were converted in accordance with the Merger Agreement, and such certificates so surrendered will be forthwith canceled, and (B) a check in an amount of U.S. dollars equal to (1) the cash portion of the Merger Consideration as described under the heading "-Merger Consideration-Effects of the Mergers," (2) any cash in lieu of fractional shares as described under the heading "-No Fractional Shares," if any, plus (3) any cash dividends or other distributions that such holder has the right to receive as described under the heading "-Distributions With Respect to Unexchanged Shares."

Distributions With Respect to Unexchanged Shares

No dividends or other distributions with respect to IonQ common stock issued in the Mergers will be paid to the holder of any unsurrendered certificates or book-entry shares until such certificates or book-entry shares are surrendered as described under the heading "-Exchange Procedures." Following surrender, there will be paid, without interest, to the record holder (i) any dividends or distributions with a record date after the Effective Time and a payment date on or before the date of surrender and not previously paid, and (ii) at the appropriate payment date, any dividends or distributions with a record date after the Effective Time but a payment date subsequent to such surrender, with all shares of IonQ common stock issued in the Mergers deemed outstanding as of the Effective Time for purposes of such dividends and distributions.

No Fractional Shares

No fractional shares of IonQ common stock will be issued upon surrender of certificates or book-entry shares evidencing SkyWater common stock, and, in lieu thereof, each holder otherwise entitled to a fractional

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IonQ share will receive a cash payment, without interest and rounded to the nearest cent, equal to such holder's proportionate interest in the net proceeds from the Exchange Agent's sale of the "Excess Shares" as described below. As soon as practicable after the Effective Time, the Exchange Agent, as agent for former SkyWater stockholders, will sell on the NYSE, at then-prevailing prices, the number of shares of IonQ common stock equal to the excess of (x) the aggregate number of shares of IonQ common stock delivered by IonQ to the Exchange Agent over (y) the aggregate number of whole shares of IonQ common stock distributable to former SkyWater stockholders (the "Excess Shares").

The Exchange Agent will hold the proceeds of such sale(s) in trust (the "Common Shares Trust") and will distribute to each former SkyWater stockholder, without interest, a cash amount equal to the product of (i) the aggregate proceeds in the Common Shares Trust multiplied by (ii) a fraction, the numerator of which is the fractional share interest to which such holder would otherwise be entitled and the denominator of which is the aggregate fractional share interests to which all holders would otherwise be entitled.

Lost, Stolen or Destroyed Certificates

In the case of any certificate that has been lost, stolen or destroyed, upon the holder's affidavit of that fact and, if required by IonQ, the First Surviving Corporation or the Surviving Company, the posting of a bond in such reasonable amount as IonQ, the First Surviving Corporation or the Surviving Company may direct as indemnity against any claim with respect to such certificate, the Exchange Agent will, if such holder has otherwise delivered a properly completed and duly executed letter of transmittal, issue in exchange for such lost, stolen or destroyed certificate the Merger Consideration to be paid in respect of the shares of SkyWater common stock represented by such certificate.

Potential Adjustments to the Merger Consideration to Prevent Dilution

If at any time during the period between the date of the Merger Agreement and the Effective Time, any change in the outstanding shares of capital stock of IonQ or SkyWater occurs by reason of any reclassification, recapitalization, stock split or combination, exchange or readjustment of shares, or any stock dividend thereon with a record date during such period, the Merger Consideration, the Per Share Cash Consideration, the Per Share Stock Consideration, the Exchange Ratio and any other similarly dependent items will be appropriately adjusted to provide holders of SkyWater common stock the same economic effect as contemplated by the Merger Agreement prior to such event. Cash dividends and grants of equity compensation not prohibited by the terms of the Merger Agreement will not result in any adjustment to the Merger Consideration, the Per Share Cash Consideration, the Per Share Stock Consideration, the Exchange Ratio or other dependent item.

Withholding

Each of the First Surviving Corporation, the Surviving Company, IonQ, SkyWater, Merger Subsidiary 1, Merger Subsidiary 2, the Exchange Agent, and any other applicable withholding agent is entitled to deduct and withhold from any payment otherwise payable to any person pursuant to the Merger Agreement such amounts as are required to be deducted or withheld under any provision of federal, state, local, or foreign tax law. To the extent that amounts are so deducted or withheld and paid over to the applicable governmental body, agency, authority or entity, such deducted or withheld amounts shall be treated for all purposes of the Merger Agreement as having been paid to the person in respect of which such deduction or withholding was made.

Treatment of SkyWater Equity Awards

SkyWater Stock Option Awards. At the Effective Time, each SkyWater Option Award that is outstanding, whether vested or unvested, will automatically be converted into an option to purchase a number of IonQ common stock based on the Equity Award Exchange Ratio at an adjusted exercise price (as determined in accordance with the formula in the Merger Agreement), and otherwise will be subject to the same terms and conditions as applied immediately prior to the Effective Time.

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Notwithstanding the foregoing, the exercise price and the number of shares of IonQ common stock purchasable pursuant to such adjusted options shall be determined in a manner consistent with the requirements of Section 409A of the Code, and, in the case of any SkyWater Option Award to which Section 422 of the Code applies, the exercise price and the number of shares of IonQ common stock purchasable pursuant to such option shall be determined subject to such adjustments as are necessary in order to satisfy the requirements of Section 424(a) of the Code.

SkyWater Employee RSU Awards. At the Effective Time, each SkyWater Employee RSU Award that is outstanding, whether vested or unvested, will automatically be converted into a restricted stock unit award corresponding to a number of IonQ common stock based on the Equity Award Exchange Ratio, and otherwise will be subject to the same terms and conditions (including any existing accelerated vesting provisions) as applied immediately prior to the Effective Time, with any related accrued but unpaid dividend equivalent rights carrying over and remaining payable in accordance with such preexisting terms.

SkyWater Director RSU Awards. Prior to the Effective Time, each SkyWater Director RSU Award that is outstanding, whether vested or unvested, will automatically become fully vested and will be settled prior to the Effective Time, and any shares of SkyWater of common stock issued thereunder will be treated in the same manner as all other shares of SkyWater common stock at the Effective Time.

Accelerated Vesting of Equity Awards Upon a Qualifying Termination. Each of the converted equity awards described above is required by the Equity Plan to provide that, if the award holder's employment or service is terminated without "cause" (as defined in the Equity Plan) by IonQ or an affiliate thereof, or by the award holder for "good reason" (as defined in the Equity Plan) (if applicable), in either case within 24 months (or, if provided in an award holder's award agreement, 12 months) following the Mergers, then effective upon the date of such termination: (1) all of the award holder's outstanding stock options shall become fully vested and exercisable in full for a period of at least 90 days or such longer period provided by such award (but not beyond the award's expiration date), (2) all time-based vesting requirements of any of the award holder's outstanding awards will be deemed satisfied in full, and (3) all performance-based vesting requirements of any of the award holder's outstanding awards for which the performance period has not yet ended will be deemed satisfied at the maximum level for such award. However, if the award holder has in effect an employment, retention, change of control, severance or similar agreement with SkyWater or any affiliate that discusses the effect of an award holder's termination of employment or service following the Mergers on the award holder's awards, then such agreement will control to the extent it provides better treatment than that described above.

SkyWater ESPP. As soon as practicable, the SkyWater Board (or, if appropriate, any committee administering the ESPP) will adopt such resolutions and take such other actions as may be required so that:

From and after the date of the Merger Agreement, SkyWater and its subsidiaries shall reasonably cooperate with IonQ in preparing such registration statements or post-effective amendments.

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Treatment of SkyWater Indebtedness

SkyWater shall deliver or cause to be delivered to IonQ at least three business days prior to the Closing Date a payoff letter (subject to the delivery of funds as arranged by IonQ) with respect to the Amended and Restated Loan and Security Agreement, dated June 30, 2025, by and between SkyWater, Siena Lending Group LLC and certain other parties (the "Subject Indebtedness"), in customary form which payoff letter shall (i) indicate the total amount required to be paid to fully satisfy all principal, interest, prepayment premiums, penalties, breakage costs and any other monetary obligations then due and payable under the Subject Indebtedness as of the anticipated Closing Date (and the daily accrual thereafter) (the "Payoff Amount"), (ii) state that upon receipt of the Payoff Amount under such payoff letter, the Subject Indebtedness and all related loan documents shall be terminated and (iii) provide that all liens and guarantees in connection with the Subject Indebtedness relating to the assets and properties of SkyWater or any of its subsidiaries securing the obligations under the Subject Indebtedness shall be released and terminated upon payment of the Payoff Amount on the Closing Date.

Covenants and Agreements

Conduct of Business

Each of IonQ and SkyWater agreed to covenants restricting, subject to specified exceptions, the conduct of its business between signing and the Effective Time (or earlier termination).

Interim Operations of SkyWater

From the date of the Merger Agreement until the Effective Time except with the prior written consent of IonQ (such consent not to be unreasonably withheld, conditioned or delayed), as expressly permitted or required by the Merger Agreement, as may be required by applicable law or as set forth in confidential disclosures exchanged between such parties, SkyWater shall and shall cause its subsidiaries to conduct their respective businesses (x) in the ordinary course consistent with past practice and (y) in a manner not involving the entry by SkyWater or its subsidiaries into businesses that are materially different from the businesses of SkyWater and its subsidiaries on the date of the Merger Agreement, and SkyWater shall use its and shall cause its subsidiaries to use their respective reasonable best efforts to keep available the services of their respective present officers and other employees, to substantially preserve their assets and technology, their relationships with customers, suppliers, licensors, licensees, distributors and other third parties having material business dealings with them and to maintain their material franchises, rights and permits.

Without limiting the foregoing, SkyWater and its subsidiaries shall, in all material respects, (A) maintain and enforce policies, procedures and internal controls reasonably designed to ensure compliance with applicable anti-corruption laws and economic sanctions/trade laws and (B) not initiate or expand any dealings involving any sanctions target or any country or territory subject to country-wide or territory-wide economic sanctions/trade laws, except as permitted by applicable law. Without limiting the generality of the foregoing, except with the prior written consent of IonQ (such consent not to be unreasonably withheld, conditioned or delayed), as expressly permitted or required by the Merger Agreement, as may be required by applicable law or as set forth in confidential disclosures exchanged between such parties, from the date of the Merger Agreement until the Effective Time, SkyWater shall not, and shall cause its subsidiaries not to:

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"Company IP" means (1) any and all intellectual property rights that are owned by or purported to be owned by SkyWater or any of its subsidiaries or exclusively licensed or purported to be exclusively licensed to SkyWater or any of its subsidiaries and (2) any technology authored, invented, created, conceived or otherwise developed by or for SkyWater or its subsidiaries, and any technology that embodies SkyWater intellectual property rights.

"Source Code" means computer programming code in human readable form that is not suitable for machine execution without the intervening steps of interpretation or compilation.

Interim Operations of IonQ

From the date of the Merger Agreement until the Effective Time, except with the prior written consent of SkyWater (such consent not to be unreasonably withheld, conditioned or delayed), as expressly permitted or required by the Merger Agreement, as may be required by applicable law or as set forth in confidential disclosures exchanged between such parties, IonQ shall not, nor shall IonQ permit any of its subsidiaries to:

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No Solicitation

Since the execution and delivery of the Merger Agreement, SkyWater has, and shall continue to cause its subsidiaries to (x) immediately cease and cause to be terminated and shall cause its and their officers and directors to, and shall use reasonable best efforts to cause its and their employees, investment bankers, consultants, attorneys, accountants, agents and other representatives to, immediately cease and cause to be terminated, any and all solicitation, encouragement, discussions or negotiations with any persons (or provision of information to any persons) with respect to any Acquisition Proposal or the possibility thereof, (y) promptly (and in any event within 24 hours) request each person and each of such person's representatives that has previously executed a confidentiality agreement with SkyWater in connection with its consideration of any Acquisition Proposal to promptly return to SkyWater or destroy all non-public information heretofore furnished or made available to such person by or on behalf of it or any of its subsidiaries and (z) immediately terminate all physical and electronic data room access for such person and its representatives to diligence or other information regarding SkyWater or any of its subsidiaries. SkyWater shall continue to enforce, and not waive, terminate or modify without IonQ's prior written consent, any confidentiality, standstill or similar provision in any confidentiality, standstill or other agreement.

"Acquisition Proposal" means any bona fide written offer or proposal for, or any bona fide written indication of interest in, any (i) direct or indirect acquisition or purchase of any business or assets of SkyWater or any of its subsidiaries that, individually or in the aggregate, constitutes 20% or more of the assets, net revenues, net income or EBITDA of SkyWater and its subsidiaries, taken as a whole, (ii) direct or indirect acquisition or purchase of 20% or more of any class of equity securities of SkyWater or any of its subsidiaries whose business constitutes 20% or more of the assets, net revenues, net income or EBITDA of SkyWater and its subsidiaries, taken as a whole, (iii) tender offer or exchange offer that, if consummated, would result in any person beneficially owning 20% or more of any class of equity securities of SkyWater or any of its subsidiaries whose business constitutes 20% or more of the assets, net revenues, net income or EBITDA of SkyWater and its subsidiaries, taken as a whole, or (iv) merger, consolidation, business combination, joint venture, partnership, recapitalization, liquidation, dissolution or similar transactions involving SkyWater or any of its subsidiaries whose business constitutes 20% or more of the assets, net revenues, net income or EBITDA of SkyWater and its subsidiaries, taken as a whole, other than the Transactions contemplated by the Merger Agreement.

During the period between the date hereof and the Effective Time or the date, if any, on which the Merger Agreement is validly terminated pursuant to Section 9.1 of the Merger Agreement, SkyWater shall continue to not, and shall continue to cause its and its subsidiaries' officers and directors not to, and shall continue to use its

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reasonable best efforts to cause its and its subsidiaries' employees, investment bankers, consultants, attorneys, accountants, agents and other representatives not to, directly or indirectly,

Nothing contained in the Merger Agreement shall prevent the SkyWater Board from

Notwithstanding anything to the contrary in the Merger Agreement but subject to the provisions described in this section titled "-No Solicitation," prior to (but not after) the receipt of SkyWater Stockholder Approval, SkyWater may, directly or indirectly through its advisors, agents or other intermediaries, (I) furnish information and access, but only in response to a request for information or access, to any person making a bona fide, written Acquisition Proposal to the SkyWater Board after the date of the Merger Agreement which was not obtained in breach of the provisions described under the section titled "-SkyWater Stockholder Meeting" or this section titled "-No Solicitation," and (II) participate in discussions and negotiate with such person or its representatives concerning any such unsolicited Acquisition Proposal, if and only if, in any such case set forth in clause (I) or (II) of this sentence, (1) the SkyWater Board concludes in good faith, after (x) receipt of the advice of a financial advisor of nationally recognized reputation and outside legal counsel that such Acquisition Proposal constitutes or would reasonably be expected to result in a Superior Proposal and (y) taking into account any revisions to the terms of the Mergers or the Merger Agreement proposed by IonQ after being notified pursuant to the Merger Agreement, that failure to do so would be reasonably likely to be inconsistent with its fiduciary duties to SkyWater's stockholders under applicable law and (2) (x) SkyWater receives from the person making such an Acquisition Proposal, prior to engaging in any of the activities described in clause (I) or clause (II) of this sentence, an executed confidentiality agreement the material terms of which, as they relate to confidentiality, non-use and other terms are (without regard to the terms of such Acquisition Proposal) in all material respects (i) no less favorable to SkyWater and (ii) no less restrictive to the person making such Acquisition Proposal than those contained in the Confidentiality Agreement (provided, that any such confidentiality agreement need not contain a standstill) and (y) any information provided to such person has previously been provided to IonQ or is provided to IonQ prior to or substantially concurrently with the time it is provided to such person. The SkyWater Board shall not take any of the actions referred to in the foregoing clause (I) and clause (II) unless SkyWater shall have first delivered to IonQ written notice advising IonQ that SkyWater intends to take such action.

"Superior Proposal" means any bona fide written Acquisition Proposal for or in respect of at least 80% of the outstanding shares of SkyWater common stock or SkyWater's and its subsidiaries' consolidated assets on

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terms that the SkyWater Board determines in its good faith judgment (after consultation with, and taking into account the advice of, a financial advisor of nationally recognized reputation and outside legal counsel, taking into account all the terms and conditions of such Acquisition Proposal, including any break-up fees, expense reimbursement provisions and conditions to consummation, as well as any revisions to the terms of the Mergers or the Merger Agreement proposed by IonQ after being notified pursuant to the provisions described in the section titled "-SkyWater Stockholder Meeting" is more favorable to SkyWater's stockholders from a financial point of view than the Mergers and the Transactions and (ii) constitutes a transaction that is likely to be consummated on the terms so proposed on a timely basis, taking into account, in the case of each of clauses (i) and (ii), all legal, financial, regulatory, financing conditionality and other aspects of such proposal.

If, on or after the date of the Merger Agreement, SkyWater receives an Acquisition Proposal, any proposal or offer that would reasonably be expected to lead to an Acquisition Proposal or any inquiry or request for nonpublic information relating to SkyWater or any subsidiary of SkyWater or for access to the properties, books or records of SkyWater or any subsidiary of SkyWater by any person that has made, or has informed SkyWater it is considering making, an Acquisition Proposal or otherwise relating to an Acquisition Proposal or that would reasonably be expected to lead to an Acquisition Proposal (in each case whether in writing or orally), SkyWater shall (i) promptly (and in no event later than 24 hours after receipt thereof) notify (which notice shall be provided orally and in writing and shall identify the person making such Acquisition Proposal, proposal, offer, inquiry or request and set forth the terms and conditions thereof) IonQ thereof, (ii) keep IonQ promptly informed of the status and terms of (including with respect to changes to the status or terms of) any such Acquisition Proposal, proposal, offer, inquiry or request, (iii) on a reasonably current basis, advise and confer with IonQ (or its outside counsel) regarding the process of negotiations concerning any Acquisition Proposal or request, and the details (including terms thereof) of any such Acquisition Proposal, proposal, offer, inquiry or request (including any changes, amendments or modifications to the terms and conditions thereof) and (iv) as promptly as practicable (but in no event later than 24 hours after receipt) provide to IonQ complete unredacted copies of all written correspondence or communications (whether or not electronic) sent or provided to SkyWater or any of its subsidiaries or its or their representatives that describes or relates to any terms or conditions thereof, including any proposed transaction agreements (along with all schedules and exhibits thereto) and written summaries of any material oral communications relating to the terms and conditions thereof.

SkyWater shall take the necessary steps promptly to inform its subsidiaries and its and their respective officers, directors, employees, investment bankers, consultants, attorneys, accountants, agents and other representatives of the obligations undertaken in provisions described in this section titled "-No Solicitation".

SkyWater Stockholder Meeting

Except as permitted by the provisions described in this section titled "-SkyWater Stockholder Meeting," the SkyWater Board shall recommend adoption of the Merger Agreement by the SkyWater's stockholders, and unless permitted by the provisions described in this section titled "-SkyWater Stockholder Meeting," neither the SkyWater Board nor any committee thereof shall (i) withdraw, modify or qualify, or propose publicly to withdraw, modify or qualify, in any manner adverse to IonQ, the approval of the Merger Agreement, the Mergers or the SkyWater recommendation (any of the foregoing, a "change in the SkyWater recommendation") or (ii) approve or recommend, or propose publicly to approve or recommend, any Acquisition Proposal. For purposes of the Merger Agreement, a change in the SkyWater recommendation shall include (x) any approval or recommendation (or public proposal to approve or recommend) of an Acquisition Proposal by the SkyWater Board or any committee thereof or (y) any failure by SkyWater to include the SkyWater recommendation in the SkyWater proxy statement.

The SkyWater Board shall be permitted at any time prior to the SkyWater Stockholder Approval being obtained, to:

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"Intervening Event" means any event, development or change in circumstances that was not known by or reasonably foreseeable to the SkyWater Board as of the date of the Merger Agreement, which event, change or development becomes known to the SkyWater Board prior to obtaining the Company Stockholder Approval; provided, that in no event shall the following events, changes or developments constitute an Intervening Event: (a) the receipt, existence or terms of an Acquisition Proposal or any matter relating thereto or consequence thereof or (b) any change in the price or trading volume of the SkyWater common stock, the IonQ common stock or any other securities of SkyWater, IonQ or any of their respective subsidiaries (provided, further, that the underlying causes of such changes may constitute, or be taken into account in determining whether there has been, an Intervening Event).

Notwithstanding the foregoing, the SkyWater Board shall not, and shall cause SkyWater not to, take any action set forth in the foregoing bullets unless, prior to taking such action,

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Except as permitted under the section titled "-No Solicitation," notwithstanding (x) any change in the SkyWater recommendation or (y) the making of any Acquisition Proposal, until the termination of the Merger Agreement (A) in no event shall SkyWater or any of its subsidiaries (1) enter into, approve or recommend or, except as set forth in the section titled "-SkyWater Stockholder Meeting," propose to approve or recommend, any letter of intent, agreement in principle, merger agreement, option agreement, acquisition agreement or other agreement constituting or relating to an Acquisition Proposal, (2) except as required by applicable law or Section 7.5 of the Merger Agreement, make, facilitate or provide information in connection with any SEC or other regulatory filings in connection with the transactions contemplated by any Acquisition Proposal or (3) seek any third-party consents in connection with any transactions contemplated by any Acquisition Proposal and (B) SkyWater shall otherwise remain subject to the terms of the Merger Agreement; provided, however, for the avoidance of doubt, that without limiting SkyWater's right to terminate the Merger Agreement in the circumstances set forth in the section titled "-Termination of the Merger Agreement," a change in the SkyWater recommendation shall not limit SkyWater's obligation to submit the Merger Agreement to the stockholders of SkyWater for the purpose of obtaining the SkyWater Stockholder Approval at the SkyWater Stockholder Meeting.

The Merger Agreement provides that the Form S-4 shall be filed with the SEC (x) no earlier than the filing with the SEC of IonQ's Annual Report on Form 10-K for fiscal year ended December 31, 2025 (which filing shall occur no later than March 2, 2026) and (y) no later than 15 days after the filing with the SEC of SkyWater's Annual Report on Form 10-K for fiscal year ended December 28, 2025. Within three business days after this Form S-4 is declared effective, SkyWater will duly call and give notice of the SkyWater Stockholder Meeting to obtain the SkyWater Stockholder Approval, with the SkyWater Board including the SkyWater recommendation in the proxy statement filed with the SEC in connection with the Mergers (the "SkyWater Proxy Statement") unless a change in the SkyWater recommendation is permitted under, and made in accordance with, the Merger Agreement's fiduciary-out provisions. SkyWater will use its reasonable best efforts to hold the SkyWater Stockholder Meeting as soon as practicable, and in any event within 40 days after the Form S-4 clearance date, and to obtain the SkyWater Stockholder Approval. SkyWater's obligation to call, notice, convene and hold the

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SkyWater Stockholder Meeting for the purpose of obtaining the SkyWater Stockholder Approval is not excused by the public proposal or communication of any Acquisition Proposal, and-absent a termination right validly exercised-SkyWater must continue to submit the Merger Agreement to stockholders even after any change in the SkyWater recommendation.

SkyWater will not, without IonQ's prior written consent, adjourn, postpone or otherwise delay the SkyWater Stockholder Meeting; provided that, after consultation with IonQ, SkyWater may adjourn or postpone (i) to solicit additional proxies to obtain the SkyWater Stockholder Approval, (ii) to distribute any supplement or amendment to the SkyWater Proxy Statement determined in good faith (with counsel) to be legally required, or (iii) for lack of a quorum, and SkyWater will use reasonable best efforts to obtain a quorum as promptly as practicable. Notwithstanding the foregoing, without IonQ's prior written consent SkyWater may not adjourn or postpone the SkyWater Stockholder Meeting more than a total of three times under the foregoing clauses or for any individual adjournment/postponement exceeding 10 business days, and may not postpone in a manner that would require setting a new record date. If adjourned or postponed, SkyWater will reconvene the meeting at the earliest practicable date on which the SkyWater Board reasonably expects to have sufficient votes to obtain the SkyWater Stockholder Approval; the only matters to be voted on will be those required for the SkyWater Stockholder Approval (and procedural/legal matters), and SkyWater will otherwise coordinate and cooperate with IonQ on meeting timing.

SkyWater will provide IonQ with updates regarding the proxy solicitation for the SkyWater Stockholder Meeting, including interim results, as reasonably requested by IonQ.

Reasonable Best Efforts

Subject to the section titled "-No Solicitation" and this section titled "-Reasonable Best Efforts," SkyWater and IonQ shall each cooperate with the other and use (and shall cause their respective subsidiaries and affiliates to use) their respective reasonable best efforts to promptly:

SkyWater and IonQ shall submit, or cause to be submitted, the notifications required under the HSR Act relating to the Mergers within 20 business days of the date of the Merger Agreement. Prior to Closing, and subject to applicable laws relating to the exchange of information, SkyWater and IonQ shall each keep the other reasonably apprised of the status of matters relating to the completion of the Mergers and work cooperatively in connection with obtaining all required approvals or consents of any governmental authority in connection with the Mergers. SkyWater and IonQ shall have the right to review in advance, and each shall consult the other to provide any necessary information with respect to all filings made with, or written materials submitted to, any third party and/or any governmental authority in connection with the Mergers and the other Transactions (other than the notifications required under the HSR Act), and each shall consider in good faith all reasonable comments suggested by the other party or its counsel in connection therewith. SkyWater and IonQ shall each promptly inform the other party, and if in writing, furnish the other party with copies (or, in the case of oral communications, advise the other party), of any material substantive communication received from any governmental authority regarding the Mergers and, subject to applicable laws, provide the other party and its

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counsel with the opportunity to participate in any meeting with any governmental authority in respect of any filing, investigation or other inquiry in connection with the Transactions contemplated hereby; provided, that notwithstanding anything to the contrary in this section titled "-Reasonable Best Efforts," and subject to IonQ's obligations to consult with SkyWater, work collaboratively with SkyWater and consider SkyWater's comments in good faith, IonQ shall control the strategy for obtaining any necessary clearance, consents, approvals or waiting period expirations or terminations pursuant to any antitrust, competition or trade regulation law that may be asserted by any governmental authority with respect to the Mergers (collectively, "Antitrust Laws") and shall lead and direct all submissions to and meetings, negotiations and communications with any governmental authority or other party in connection with matters with respect to any Antitrust Law, and shall do so in a manner reasonably designed to obtain any such clearance, consents, approvals or waiting period expirations or terminations as promptly as reasonably practicable and, in any event, prior to January 25, 2027 (which is the "End Date") or the Extended End Date (as defined herein), as applicable.

No party shall agree to "pull-and-refile" any filing made under the HSR Act or otherwise consent or agree to any timing agreement, extension or tolling of any waiting period or any other voluntary delay of the Mergers or Transactions contemplated hereby without the prior written consent of the other parties, which consent shall not be unreasonably withheld. If either IonQ or SkyWater, or any of their respective affiliates, receives a request for additional information or documentary material from any governmental authority with respect to the Mergers, then such party shall use its reasonable best efforts to make, or cause to be made, promptly and after consultation with the other party, an appropriate response in substantial compliance with such request. Subject to applicable laws or any request made by any applicable governmental authority (including the staff thereof), SkyWater and IonQ shall each furnish to each other copies of all material substantive correspondence, filings (other than the notifications required under the HSR Act) and written communications between it and any such governmental authority with respect to the Merger Agreement and the Mergers, and furnish the other party with such necessary information and reasonable assistance as the other party may reasonably request in connection with its preparation of filings or submissions of information to any such governmental authority; provided, that materials provided pursuant to the provisions described in this section titled "-Reasonable Best Efforts" may be redacted (x) to remove references concerning the valuation of SkyWater, (y) as necessary to comply with applicable law or contractual obligations and (z) as necessary to address reasonable privilege or confidentiality concerns.

Without limiting the provisions described in this section titled "-Reasonable Best Efforts," IonQ and SkyWater shall, as applicable:

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IonQ and, if requested by IonQ, SkyWater shall agree to any such Divestiture Remedies or Behavioral Remedies; provided, however, that notwithstanding anything to the contrary in the Merger Agreement, neither IonQ nor SkyWater shall be required to (and SkyWater and SkyWater's subsidiaries shall not, without the prior written consent of IonQ) take, commit or agree to (A) any Behavioral Remedy or Divestiture Remedy that is not expressly conditioned on the Closing, (B) any Behavioral Remedy or Divestiture Remedy that relates to the operations, activities or businesses of IonQ or its subsidiaries prior to the Closing or (C) any Divestiture Remedy that would reasonably be expected to have a material adverse effect on SkyWater and its subsidiaries (measured as a whole). SkyWater shall not negotiate, commit to or effectuate any Divestiture Remedy, any Behavioral Remedy or any other sale, divestiture or disposal of businesses, product lines or assets of SkyWater or SkyWater's subsidiaries or any exclusive license of material Company IP, without IonQ's prior written consent; provided, that the foregoing shall not relieve any party of its obligations under the Merger Agreement. For avoidance of doubt, no undertakings or actions pursuant to the provisions described in this section titled "-Reasonable Best Efforts" shall constitute a SkyWater material adverse effect or IonQ material adverse effect or entitle IonQ to any reduction or offset to the Merger Consideration.

SkyWater and IonQ shall cooperate with one another (a) in determining whether any action by or in respect of, or filing with, any governmental authority is required, or any actions, consents, approvals or waivers are required to be obtained from parties to any Material Contracts, in connection with the consummation of the Transactions and (b) in seeking any such actions, consents, approvals or waivers or making any such filings, furnishing information required in connection therewith or with the SkyWater Proxy Statement or the Form S-4 and seeking timely to obtain any such actions, consents, approvals or waivers. Subject to the provisions described in this section titled "-Reasonable Best Efforts," in no event shall IonQ, the Merger Subsidiaries, SkyWater or any subsidiary of SkyWater or IonQ be required to pay, make or commit to pay or make (and without the prior written consent of IonQ, none of SkyWater or any subsidiary of SkyWater shall pay, make or commit to pay or make), any fee (other than required filing fees), penalty or other consideration or any other accommodation to any third party to obtain any consent, approval or waiver in connection with the Transactions under any contract with such third party.

Employee Benefits

From and after the Effective Time, IonQ shall cause the Surviving Company to honor in accordance with their terms all benefits and obligations under the SkyWater Benefit Plans, each as in effect on the date of the Merger Agreement, to the extent that entitlements or rights, actual or contingent (whether such entitlements or rights are vested as of the Effective Time or become vested or payable only upon the occurrence of a further event) exist in respect thereof as of the Effective Time. The consummation of the Mergers shall constitute a "Change in Control" for purpose of any employee arrangement and all other SkyWater Benefit Plans, pursuant to the terms of such plans in effect on the date of the Merger Agreement. None of the foregoing shall be construed as a limitation on the right of IonQ to amend or terminate any SkyWater Benefit Plans which SkyWater would otherwise have under the terms of such SkyWater Benefit Plan, and none of the foregoing shall be construed to create a right in any employee or beneficiary of such employee under a SkyWater Benefit Plan that such employee or beneficiary would not otherwise have under the terms of such plan.

For a period of one year following the Effective Time, IonQ shall continue to provide to each individual who is employed by the Surviving Company or its subsidiaries as of the Closing Date and who remains employed with IonQ or any subsidiary of IonQ ("Affected Employees"), for so long as such Affected Employee remains employed by IonQ or any subsidiary of IonQ, (i) an annual base salary or base wage rate that is no less than the annual base salary or base wage rate provided to the Affected Employee immediately prior to the Closing Date, (ii) cash incentive opportunities that are substantially comparable in the aggregate to those provided to such Affected Employee immediately prior to the Closing Date, and (iii) employee benefits that are substantially comparable in the aggregate to those provided to such Affected Employee immediately prior to the Closing Date. Notwithstanding the terms discussed in the immediately prior paragraph, IonQ shall, or shall cause the Surviving Company or another its subsidiaries to, (i) honor the terms of the annual cash bonus program for

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2026 as in effect at the Closing Date (which is the 2026 Bonus Program) and (ii) determine the amount payable under the 2026 Bonus Program in a manner consistent with SkyWater's past practices, except that, in each case, any bonus payable under the 2026 Bonus Program shall be prorated based on a fraction, the numerator of which is the number of days between January 1, 2026 and the Closing Date (including the Closing Date) and the denominator of which is 365.

IonQ shall, or shall cause the Surviving Company or another of its subsidiaries to, give each Affected Employee full credit for purposes of eligibility, vesting and benefit accrual (other than benefit accruals under any defined benefit pension or post-employment or retiree health or welfare plan that, in each case, is not a SkyWater Benefit Plan) under any employee benefit plans or arrangements maintained by IonQ or any subsidiary of IonQ for such Affected Employees' service with SkyWater or any subsidiary to the same extent recognized by SkyWater or its applicable subsidiary immediately prior to the Effective Time, except to the extent that such credit would result in a duplication of benefits or compensation for the same period of service.

"SkyWater Benefit Plans" mean (i) each material "employee benefit plan," as defined in Section 3(3) of ERISA, each (ii) material employment, consulting, severance, change in control or similar contract, plan, funding vehicle or arrangement or policy applicable to any director, former director, employee or former employee of SkyWater or any of its subsidiaries, and (iii) each other material plan or arrangement (written or oral), providing for compensation, bonuses, profit-sharing, stock option or other stock-related rights or other forms of incentive or deferred compensation, vacation benefits, insurance coverage (including any self-insured arrangements), health or medical benefits, death benefits, disability benefits, workers' compensation, supplemental unemployment benefits, severance benefits, change in control benefits and post-employment or retirement benefits (including compensation, pension, health, medical or life insurance benefits), in each case which is maintained, administered or contributed to by SkyWater or its subsidiaries and covers any employee or director or former employee or director of SkyWater or any of its subsidiaries, other than any such arrangements which are required by law (such as Social Security contributions), excluding any such plan that is a "multiemployer plan," as defined in Section 3(37) of ERISA).

IonQ shall, or shall cause the Surviving Company to, (i) waive all limitations as to preexisting conditions, exclusions and waiting periods with respect to participation and coverage requirements applicable to the Affected Employees under any welfare benefit plans in which such employees may be eligible to participate after the Effective Time (the "Successor Welfare Plans"), other than limitations or waiting periods that are already in effect with respect to such employees and that have not, as of the date the Affected Employees become eligible for the Successor Welfare Plans, been satisfied under any welfare plan maintained for the Affected Employees immediately prior to the date of such eligibility, and (ii) for the year in which a Successor Welfare Plan that is a group health plan replaces any SkyWater Benefit Plan that is a group health plan, provide each Affected Employee with credit under such Successor Welfare Plan for any co-payments and deductibles paid by the Affected Employee under the similar SkyWater Benefit Plan prior to the date the Affected Employee becomes covered by such Successor Welfare Plan in satisfying any applicable deductible or out-of-pocket requirements under the Successor Welfare Plan.

If requested by IonQ in writing delivered to SkyWater not less than 10 business days prior to the Closing Date, SkyWater and each of its subsidiaries shall adopt resolutions and take all such corporate action as is necessary to terminate each benefit plan intended to qualify pursuant to Section 401(k) of the Code that is maintained, sponsored or contributed to by SkyWater or any of its subsidiaries (collectively, the "SkyWater 401(k) Plans"), in each case, effective as of the day immediately prior to the Closing Date, and SkyWater shall provide IonQ with evidence that such SkyWater 401(k) Plans have been properly terminated, with the form of such termination documents subject to the reasonable approval of IonQ. If any SkyWater 401(k) Plan is terminated pursuant to IonQ's request, the applicable Affected Employees shall be eligible to participate in a benefit plan intended to qualify pursuant to Section 401(k) of the Code that is maintained by IonQ or one of its subsidiaries as soon as reasonably practicable following the Closing Date, and such Affected Employees shall be entitled to effect a direct rollover of any eligible rollover distributions (as defined in Section 402(c)(4) of the Code), including any outstanding loans, to such plan maintained by IonQ or its subsidiaries.

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Nothing in the provisions described in this section titled "-Employee Benefits" express or implied, shall (i) be construed to establish, amend or modify any benefit or compensation plan, program, agreement, contract, policy or arrangement, (ii) limit the ability of IonQ, SkyWater or any of their respective subsidiaries or affiliates to amend, modify or terminate any benefit or compensation plan, program, agreement, contract, policy or arrangement at any time assumed, established, sponsored or maintained by any of them, except as permitted by the terms of such plan, program, agreement, contract, policy or arrangement, (iii) create any third-party beneficiary rights or obligations in any person (including any employee) or any right to employment or service or continued employment or service or to a particular term or condition of employment or service with IonQ or SkyWater or any of their respective subsidiaries or affiliates or (iv) limit the right of IonQ or SkyWater (or any of their respective subsidiaries or affiliates) to terminate the employment or service of any employee or other service provider following the Closing at any time and for any or no reason.

Upon IonQ's reasonable request from time to time, SkyWater shall, within a reasonable period of time following receipt of such request (but in no event more than five business days following receipt of such request), provide IonQ with the then-most recent calculations and reasonable backup information relating to Section 280G and Section 4999 of the Code relating to the Transactions, including any non-compete valuations.

Following the date of the Merger Agreement, to the extent applicable, SkyWater shall provide IonQ with a list of employees who would be affected by any facility closings or employee layoffs or reductions in force that would trigger the notice requirements under the WARN Act and that would occur between the date of the Merger Agreement and the Closing Date.

Director and Officer Liability

Without limiting any other rights that any Indemnified Person may have pursuant to any employment agreement or indemnification agreement, from the Effective Time and until the six-year anniversary of the Effective Time, IonQ shall cause the Surviving Company and each of its subsidiaries to indemnify, defend and hold harmless each person who is now, or has been at any time prior to the date of the Merger Agreement or who becomes prior to the Effective Time, a director, officer or employee of SkyWater or of such subsidiary, as applicable, or who acts as a fiduciary under any SkyWater Benefit Plan or is or was serving at the request of SkyWater or of such subsidiary as a director, officer, employee or agent of another corporation, partnership, limited liability company, joint venture, employee benefit plan, trust or other enterprise (the "Indemnified Persons") against all losses, claims, damages, costs, fines, penalties, expenses (including attorneys' and other professionals' fees and expenses), liabilities or judgments or amounts that are paid in settlement of or incurred in connection with any threatened or actual claim (including a claim of a violation of applicable law), action, audit, demand, suit, proceeding, investigation or other proceeding at law or in equity or order or ruling, in each case whether civil, criminal, administrative, investigative or otherwise and whether or not such claim, action, audit, demand, suit, proceeding, investigation or other proceeding or order or ruling results in a formal civil or criminal litigation or regulatory action ("Proceeding") to which such Indemnified Person is a party or is otherwise involved (including as a witness) based, in whole or in part, on or arising, in whole or in part, out of the fact that such person is or was a director, officer or employee of SkyWater or of such subsidiary, a fiduciary under any SkyWater Benefit Plan or is or was serving at the request of SkyWater or of such subsidiary as a director, officer, employee or agent of another corporation, partnership, limited liability company, joint venture, employee benefit plan, trust or other enterprise or by reason of anything done or not done by such person in any such capacity, whether pertaining to any act or omission occurring or existing prior to, at or after the Effective Time and whether asserted or claimed prior to, at or after the Effective Time ("Indemnified Liabilities"), including all Indemnified Liabilities based in whole or in part on, or arising in whole or in part out of or pertaining to the Merger Agreement or the Transactions, in each case to the fullest extent permitted under applicable law (and IonQ shall cause the Surviving Company or such subsidiary to pay expenses incurred in advance of the final disposition of any such Proceeding to each Indemnified Person to the fullest extent permitted under applicable law).

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Any Indemnified Person wishing to claim indemnification or advancement of expenses under the provisions described in this section titled "-Director and Officer Liability," upon learning of any such Proceeding, shall notify the Surviving Company (but the failure so to notify shall not relieve a party from any obligations that it may have under the provisions described in this section titled "-Director and Officer Liability" except to the extent such failure materially prejudices such party's position with respect to such claims). IonQ shall have the right, upon written notice to any applicable Indemnified Person, to assume the defense of any Proceeding in respect of which indemnification is or would be sought hereunder employing counsel reasonably satisfactory to such Indemnified Person. Notwithstanding anything to the contrary in the provisions described in this section titled "-Director and Officer Liability," an Indemnified Person shall only be entitled to the rights provided in the provisions described in this section titled "-Director and Officer Liability" after providing a written undertaking by or on behalf of such Indemnified Person to repay such amounts if it is ultimately determined under applicable law that such Indemnified Person is not entitled to be indemnified.

IonQ and the Surviving Company shall not amend, repeal or otherwise modify any provision in the organizational documents of the Surviving Company or its subsidiaries in any manner that would adversely affect the rights thereunder of any Indemnified Person to indemnification, exculpation or expense advancement, except to the extent required by applicable law. IonQ shall cause the Surviving Company and its subsidiaries to fulfill and honor any indemnification, expense advancement or exculpation agreements between SkyWater or any of such subsidiaries and any of its or their directors, officers or employees existing immediately prior to the Effective Time.

To the fullest extent permitted under applicable law, IonQ shall cause the Surviving Company and each of its subsidiaries to indemnify any Indemnified Person against all reasonable costs and expenses (including reasonable attorneys' fees and expenses), such amounts to be payable in advance upon request as provided in the provisions described in this section titled "-Director and Officer Liability," relating to the enforcement of such Indemnified Person's rights under the provisions described in this section titled "-Director and Officer Liability"; provided, that, any such Indemnified Person shall only be entitled to the rights of advancement provided in this section titled "-Director and Officer Liability" after providing a written undertaking by or on behalf of such Indemnified Person to repay such amounts if it is ultimately determined under applicable law that such Indemnified Person is not entitled to be indemnified.

IonQ shall cause the Surviving Company to put in place, and IonQ shall fully prepay no later than immediately prior to the Closing, "tail" insurance policies with a claims reporting or discovery period of at least six years from the Effective Time placed with insurance companies having the same or better AM Best Financial rating as SkyWater's current directors' and officers' liability insurance companies with terms and conditions providing retentions, limits and other material terms no less favorable than the current directors' and officers' liability insurance policies maintained by SkyWater with respect to matters, acts or omissions existing or occurring at or prior to the Effective Time; provided, however, that IonQ may elect, in its sole discretion, but shall not be required, to spend more than the amount set forth on confidential disclosures exchanged between such parties (the "Cap Amount") for the six years of coverage under such "tail" policy; provided, further, that, if the cost of such insurance exceeds the Cap Amount and IonQ elects not to spend more than the Cap Amount for such purpose, then IonQ shall purchase as much coverage as is reasonably available for the Cap Amount.

If IonQ or the Surviving Company (i) consolidates with or merges into any other person and shall not be the continuing or surviving corporation or entity of such consolidation or Mergers or (ii) transfers all or substantially all of its properties and assets to any person, then, in each such case, proper provisions shall be made so that the successors and assigns of the Surviving Company, as the case may be, shall assume the obligations set forth in the provisions described in this section titled "-Director and Officer Liability". IonQ and the Surviving Company shall not sell, transfer, distribute or otherwise dispose of any of their assets or the assets of any subsidiary in a manner that would reasonably be expected to render IonQ or Surviving Company unable to satisfy their obligations under the provisions described in this section titled "-Director and Officer Liability". The provisions described in this section titled, "-Director and Officer Liability" are intended to be for the benefit of, and shall be enforceable by, the parties and any Indemnified Persons and their heirs and representatives.

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Other Covenants

The Merger Agreement contains certain other covenants and agreements, including covenants and agreements relating to, among other matters:

Representations and Warranties

SkyWater makes various representations and warranties with respect to itself and its subsidiaries to IonQ and the Merger Subsidiaries in the Merger Agreement that are subject in some cases to exceptions and qualifications. These representations and warranties relate to, among other things:

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In addition, IonQ and the Merger Subsidiaries make representations and warranties to SkyWater. These representations and warranties relate to, among other things:

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The representations and warranties in the Merger Agreement do not survive the consummation of the Mergers or termination of the Merger Agreement. Many of the representations and warranties in the Merger Agreement are qualified by a "knowledge," "materiality" or "material adverse effect" standard (that is, they will not be deemed to be untrue or incorrect unless their failure to be true or correct, individually or in the aggregate, would, as the case may be, be material or have a material adverse effect). For purposes of the Merger Agreement, a "Company Material Adverse Effect" or "Parent Material Adverse Effect," as applicable, means any state of facts, change, development, event, effect, condition or occurrence that, individually or in the aggregate, (x) has resulted or would reasonably be expected to result in a material adverse effect on the condition (financial or otherwise), business, assets or continuing results of operations of SkyWater and its subsidiaries or IonQ and its subsidiaries, as applicable, taken as a whole, or (y) has prevented, materially impeded or materially delayed or would reasonably be expected to prevent, materially impede or materially delay the consummation by SkyWater, IonQ or the Merger Subsidiaries of the Mergers. None of the following, among other things, alone or in combination, will be deemed to constitute, or be taken into account in determining whether there has been, a material adverse effect for the purposes of clause (x) above:

However, the exceptions in the three immediately preceding bullets will not prevent or otherwise affect a determination that the underlying cause of any such change, decline or failure referred to therein (if not otherwise falling within any of the other exceptions) is a material adverse effect. In addition, in the case of the first four bullets above, to the extent the impact on SkyWater or IonQ, as applicable, and their respective subsidiaries, taken as a whole, is disproportionately adverse compared to the impact on similarly situated entities in the industry in which SkyWater or IonQ and their respective subsidiaries operate, the incrementally disproportionate impact or impacts will be taken into account in determining whether there has been, or would reasonably be expected to be, a material adverse effect.

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Conditions to Completion of the Mergers

The respective obligations of each party to the Merger Agreement to effect the Mergers at the Closing as contemplated by the Merger Agreement will be subject to the fulfillment (or, to the extent permitted by law, waiver) at or prior to the Effective Time of the following conditions:

The obligations of IonQ and the Merger Subsidiaries to effect the Mergers at the Closing as contemplated by the Merger Agreement are further subject to the fulfillment (or, to the extent permitted by law, waiver) of the following conditions:

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The obligation of SkyWater to effect the Mergers at the Closing as contemplated by the Merger Agreement is further subject to the fulfillment (or, to the extent permitted by law, waiver) of the following conditions:

Termination of the Merger Agreement

Termination Rights of SkyWater and IonQ

The Merger Agreement may be terminated and the Mergers may be abandoned at any time prior to the Effective Time (notwithstanding the obtaining of SkyWater Stockholder Approval):

if the Mergers have not been consummated by the End Date; provided, that (A) if on such date, the conditions to the Closing set forth in Section 8.1(b) (HSR Act waiting period) or Section 8.1(c) (No Legal Restraint Condition, where the failure is a result of any law, regulation, judgment, injunction, order or decree arising under any Antitrust Law) shall not have been satisfied, but all other conditions to the Closing shall have been satisfied or validly waived (except for those conditions that by their terms must be satisfied at the Closing; provided, that such conditions are capable of being satisfied at the Closing), then the End Date shall be automatically extended for a period of 90 days and (B) if on such date as extended pursuant to the foregoing clause (A), the same conditions shall not have been satisfied, but all other conditions to the Closing shall have been satisfied or validly waived, then the End Date shall be automatically extended for an additional period of 90 days (the End Date, as it may be so extended, the "Extended End Date"); provided, however, that the right to terminate the Merger Agreement under this provision shall not be available to any party whose failure to fulfill any obligation under the Merger Agreement has principally caused or resulted in the failure of the Effective Time to occur on or before the End Date or the Extended End Date, as applicable; or

if the SkyWater Stockholder Approval shall not have been obtained by reason of the failure to obtain the required vote at a duly held meeting of stockholders or any adjournment thereof;

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at any time prior to receipt of the SkyWater Stockholder Approval, if there shall have been a change in the SkyWater recommendation, whether or not permitted by the terms of the Merger Agreement (or the SkyWater Board or any committee thereof shall resolve to effect a change in the SkyWater recommendation); or

if SkyWater has breached or failed to perform in any material respect any of its representations, warranties, covenants or agreements contained in the Merger Agreement, which breach or failure to perform (A) would result in a failure of a condition set forth in Section 8.2(a) of the Merger Agreement (the SkyWater accuracy of representations and warranties condition or the SkyWater Covenant Performance Condition) and (B) is incapable of being cured or, if capable of being cured, shall not have been cured within 30 days after written notice thereof shall have been received by SkyWater; and

if IonQ has breached or failed to perform in any material respect any of its representations, warranties, covenants or agreements contained in the Merger Agreement, which breach or failure to perform (A) would result in a failure of a condition set forth in Section 8.3(a) of the Merger Agreement (IonQ accuracy of representations and warranties condition or IonQ Covenant Performance Condition) and (B) is incapable of being cured or, if capable of being cured, shall not have been cured within 30 days after written notice thereof shall have been received by IonQ (Section 9.1(e) of the Merger Agreement); or

at any time prior to receipt of the SkyWater Stockholder Approval in order to enter into a definitive written agreement providing for a Superior Proposal; provided, that (i) SkyWater has received a Superior Proposal after the date of the Merger Agreement that did not result from a breach of Section 5.2 or Section 5.3 of the Merger Agreement, (ii) SkyWater has complied with Section 5.3(b)(i) of the Merger Agreement with respect to such Superior Proposal, (iii) concurrently with, and as a condition to, any such termination SkyWater pays or causes to be paid to IonQ (or its designee) the Termination Fee pursuant to Section 10.5 of the Merger Agreement and (iv) the SkyWater Board has authorized SkyWater to enter into, and SkyWater concurrently enters into, a definitive written agreement providing for such Superior Proposal.

The party desiring to terminate the Merger Agreement (other than by mutual written consent) shall give written notice of such termination to the other party in accordance with Section 10.1 of the Merger Agreement, specifying the provision pursuant to which such termination is affected. If the Merger Agreement is terminated pursuant to Section 9.1 of the Merger Agreement, the Merger Agreement shall become void and of no effect with no liability on the part of any party, except that (a) the agreements contained in Section 9.2, Section 10.4, Section 10.5 and Section 10.6 of the Merger Agreement, and the confidentiality letter agreement dated as of December 21, 2025, between IonQ and SkyWater, as amended, shall survive the termination and (b) no such termination shall relieve any party of any liability or damages resulting from any material and intentional breach by that party of the Merger Agreement.

Termination Fees

If:

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then SkyWater shall pay (or cause to be paid) to IonQ (by wire transfer of immediately available funds), (x) in the cases described in the first and third bullets above, $51,573,958.07 (which is the "Termination Fee") not later than the date of termination of the Merger Agreement and (y) in the case described in the second bullet above, SkyWater shall pay (or cause to be paid) an amount equal to the Termination Fee not later than the earlier of the date an Acquisition Proposal is consummated or a definitive agreement is entered into by SkyWater providing for any Acquisition Proposal, as long as, in either case, such Acquisition Proposal is consummated or such definitive agreement is executed within 12 months after the date of termination of the Merger Agreement; provided, however, that for the purpose of this clause (y), all references in the definition of Acquisition Proposal to 20% shall instead refer to 50%. The Termination Fee represents approximately [ ]% of SkyWater's equity value (calculated as $[ ] per share of SkyWater common stock, based on the closing price on [     ], 2026 multiplied by [ ] shares of SkyWater common stock outstanding as of [ ]).

If SkyWater fails to pay timely any amount due pursuant to the provisions of the Merger Agreement described in this section titled "-Termination Fees" and, in order to obtain such payment, IonQ commences a suit which results in a judgment against SkyWater for the amount payable to IonQ pursuant to this section, SkyWater shall pay to IonQ its reasonable costs and expenses (including attorneys' fees and expenses) in connection with such suit, together with interest on the amount so payable at the rate on six-month United States Treasury obligations (as of the date such payment was required to be made pursuant to the Merger Agreement) plus three percent.

The Merger Agreement does not provide for a reverse termination fee payable by IonQ to SkyWater under any circumstances. In the event of an Antitrust Termination, SkyWater's sole and exclusive remedy against IonQ is the right to cause IonQ to consummate the equity investment described under "-Equity Investment Following Antitrust Termination" below.

Equity Investment Following Antitrust Termination

Additionally, in the event of a termination following failure to obtain the required regulatory approvals for the Mergers and to resolve or eliminate impediments under Antitrust Laws by the End Date or the Extended End Date, as applicable ("Antitrust Termination"), SkyWater will be required to issue to IonQ (or a subsidiary), and IonQ (or a subsidiary) will be required to purchase from SkyWater, an aggregate of 2,857,143 newly issued shares of SkyWater common stock (the "Investment Shares") for $100,000,000. SkyWater will use reasonable best efforts to cause the Investment Shares to be approved for listing on the Nasdaq Stock Exchange and to facilitate Rule 144 resales and the removal of restrictive legends, subject to customary conditions and allocations of costs. For up to two years following such equity investment (or earlier if IonQ no longer owns the Investment Shares), IonQ will be subject to a customary standstill, on the terms provided in the Merger Agreement, and may vote the Investment Shares in its sole discretion. SkyWater's right to cause IonQ or any of its affiliates to

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consummate the purchase of the Investment Shares shall be the sole and exclusive remedy of SkyWater against IonQ, the Merger Subsidiaries, their respective subsidiaries, and their respective directors, officers, employees and affiliates for any losses or damages suffered as a result of the failure of the Closing to occur due to the failure of the conditions to obtain the required regulatory approvals for the Mergers and to resolve or eliminate impediments under Antitrust Laws.

Expenses

Except as described under the heading "Termination Fees" or as otherwise agreed to in writing by the parties, all costs and expenses incurred in connection with the Merger Agreement and the Transactions will be paid by the party to the Merger Agreement incurring such cost or expense, except that (x) expenses incurred in connection with printing, mailing and filing the Form S-4, (y) all filing fees paid in respect of filings under the HSR Act or other Antitrust Laws in connection with the Transactions and (z) all reasonable and documented fees, costs and expenses incurred in connection with any cooperation provided or action taken pursuant to Section 5.8 of the Merger Agreement (Treatment of SkyWater Indebtedness) or in connection with any financing to be obtained by IonQ relating to the repayment or refinancing of any outstanding indebtedness of SkyWater shall, in each case, be borne by IonQ.

Amendments, Waivers

At any time prior to the Effective Time, any provision of the Merger Agreement (including its Exhibits and Schedules) may be amended or waived if, and only if, such amendment or waiver is in writing and signed, in the case of an amendment, by SkyWater, IonQ and the Merger Subsidiaries, or in the case of a waiver, by the party against whom the waiver is to be effective; provided, that after the adoption of the Merger Agreement by the stockholders of SkyWater, there shall be no amendment or waiver of the Merger Agreement which would by law require further approval by the stockholders of SkyWater without such approval of such stockholders. No failure or delay by any party in exercising any right, power or privilege under the Merger Agreement shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any other right, power or privilege. The rights and remedies provided in the Merger Agreement shall be cumulative and not exclusive of any rights or remedies provided by law.

Governing Law; Jurisdiction; Waiver of Jury Trial

The Merger Agreement and all claims or causes of action (whether in tort, contract or otherwise) that may be based upon, arise out of or relate to the Merger Agreement or the negotiation, execution or performance of the Merger Agreement (including any claim or cause of action based upon, arising out of or related to any representation or warranty made in or in connection with the Merger Agreement) will be governed by and construed in accordance with the laws of the State of Delaware, without giving effect to any choice or conflict of law provision or rule that would cause the application of the laws of any jurisdiction other than the State of Delaware.

In addition, each of the parties to the Merger Agreement has agreed that any suit, action or proceeding seeking to enforce any provision of, or based on any matter arising out of or in connection with, the Merger Agreement or the Transactions may only be brought in the Court of Chancery of the State of Delaware (or, only if such court declines to accept jurisdiction over a particular matter, then in the United States District Court for the District of Delaware or, if jurisdiction is not then available in the United States District Court for the District of Delaware, then in any court sitting of the State of Delaware in New Castle County) and any appellate court from any of such courts (the "Delaware Court"). Each of the parties to the Merger Agreement has consented to the exclusive jurisdiction of the applicable Delaware Court in any such suit, action or proceeding and irrevocably waives, to the fullest extent permitted by law, any objection which it may now or hereafter have to the laying of the venue of any such suit, action or proceeding in any such court or that any such suit, action or proceeding which is brought in any such court has been brought in an inconvenient forum. Process in any such suit, action or

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proceeding may be served on any party anywhere in the world, whether within or without the jurisdiction of the applicable Delaware Court. Each party has agreed that service of process upon such party in any such action or proceeding will be effective if such process is given as a notice in accordance with the notice provisions set forth in the Merger Agreement or in any other manner permitted by applicable law.

Each party to the Merger Agreement has irrevocably waived any and all right to a trial by jury in any legal proceeding arising out of or relating to the Merger Agreement or the Transactions.

Specific Performance

The parties to the Merger Agreement have agreed that irreparable damage would occur in the event that any of the provisions of the Merger Agreement were not performed in accordance with their specific terms or were otherwise breached. Accordingly, the parties to the Merger Agreement will be entitled to specific performance of the terms of the Merger Agreement, in addition to any other remedy at law or equity.

Third-Party Beneficiaries

The Merger Agreement does not confer any rights or remedies upon any person other than the parties thereto and their permitted assigns, except for (i) the right of former holders of SkyWater common stock to receive the Merger Consideration and (ii) the right of SkyWater's current and former directors and officers to indemnification and exculpation from liability as described under "-Other Covenants."

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THE VOTING AGREEMENT

Pursuant to the Voting Agreement, among other things, each Voting Agreement Holder has agreed, from the date of the Voting Agreement until the Voting Agreement Termination Date (as defined below), to vote (or cause to be voted) all shares of SkyWater common stock owned of record or beneficially by such Voting Agreement Holder (the "Covered Shares"):

In addition, each Voting Agreement Holder has agreed, from the date of the Voting Agreement until the Voting Agreement Termination Date, to appear, in person or by proxy, at each meeting of the stockholders of SkyWater or adjournment or postponement thereof (or otherwise cause its Covered Shares to be counted as present thereat) for purposes of calculating a quorum.

Notwithstanding the foregoing, each Voting Agreement Holder remains free to vote (or execute proxies with respect to) the Covered Shares with respect to any matter not covered by Section 3 of the Voting Agreement in any manner that such Voting Agreement Holder deems appropriate. The voting obligations of the Voting Agreement Holders do not require any Voting Agreement Holder to vote any of its Covered Shares to amend, modify or waive any provision of the Merger Agreement, without such Voting Agreement Holder's consent, in a manner that (i) reduces the amount or changes the form of the Merger Consideration payable or (ii) imposes any express material restrictions on or express additional material conditions on the payment of the Merger Consideration (each, an "Adverse Amendment").

Transfer Restrictions

From the date of the Voting Agreement until the Voting Agreement Termination Date, each Voting Agreement Holder has agreed not to transfer (or cause or knowingly permit the transfer of) any of the Covered Shares; provided, that any Voting Agreement Holder may transfer any Covered Shares:

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provided, that, in each case, of the first five bullets above, the transferee of such Covered Shares evidences in writing reasonably satisfactory to IonQ such transferee's agreement to be bound by and be subject to the terms and provisions of the Voting Agreement to the same effect as the transferring Voting Agreement Holder.

Each Voting Agreement Holder has authorized SkyWater or its counsel to impose stop transfer orders on the Covered Shares to prevent any transfer in violation of the Voting Agreement.

Waiver of Appraisal Rights

Each Voting Agreement Holder has waived any rights of appraisal or rights to dissent from the Mergers that such Voting Agreement Holder may have under applicable law.

Termination

The Voting Agreement will terminate upon the "Voting Agreement Termination Date," which is the earliest to occur of:

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INFORMATION ABOUT THE COMPANIES

IonQ

IonQ, Inc. is the world's first and only quantum platform company. It operates in every theater: in space, in the air, on land and at sea, where it seeks to deliver the full promise of quantum, across computing, networking, sensing and security. It believes that it has the clearest path to fault-tolerant quantum computing, and a repertoire of networking, sensing and security products that will form the backbone of a global quantum infrastructure. In 2025, it achieved 99.99% two-qubit gate fidelity, setting a world record in quantum computing performance.

Headquartered in College Park, Maryland, IonQ has operations in California, Colorado, Massachusetts, Tennessee, Washington, Italy, South Korea, Sweden, Switzerland, Toronto and the United Kingdom. IonQ's quantum computing services are available through all major cloud providers, while IonQ also meets the needs of networking and sensing customers across land, sea, air and space.

IonQ is incorporated in Delaware. Its principal executive offices are located at 4505 Campus Drive, College Park, Maryland 20740, and its telephone number is (301) 298-7997. IonQ's website address is www.ionq.com. Information contained on IonQ's website does not constitute part of this proxy statement/prospectus. IonQ's common stock is publicly traded on the NYSE under the ticker symbol "IONQ."

Additional information about IonQ is included in documents incorporated by reference in this proxy statement/prospectus. See "Where You Can Find More Information" beginning on page [ ].

SkyWater

SkyWater is securing America's silicon foundation as the largest U.S.-based, pure-play semiconductor foundry. A trusted partner to both commercial customers and federal defense programs, SkyWater's Technology as a Service model empowers innovators to bring emerging technologies like quantum computing and next-generation systems from concept to reality. With state-of-the-art facilities in Minnesota, Florida and Texas, SkyWater specializes in foundational nodes and advanced packaging to support the nation's critical infrastructure, strengthen supply chain resilience, and ensure long-term U.S. technology leadership. SkyWater is a DMEA-accredited Category 1A Trusted Foundry.

SkyWater is incorporated in Delaware. Its principal executive offices are located at 2401 East 86th Street, Bloomington, Minnesota 55425, and its telephone number is (952) 851-5200. SkyWater's website address is www.skywatertechnology.com. Information contained on SkyWater's website does not constitute part of this proxy statement/prospectus. SkyWater's common stock is publicly traded on Nasdaq under the ticker symbol "SKYT." Additional information about SkyWater is included in documents incorporated by reference in this proxy statement/prospectus. See "Where You Can Find More Information" beginning on page [ ].

Merger Subsidiary 1

Merger Subsidiary 1, a direct wholly-owned subsidiary of IonQ, is a Delaware corporation incorporated on January 22, 2026 for the purpose of effecting the First Merger. Merger Subsidiary 1 has not conducted any activities other than those incidental to its formation and the matters contemplated by the Merger Agreement, including the preparation of applicable regulatory filings in connection with the Transactions. The principal executive offices of Merger Subsidiary 1 are located at 4505 Campus Drive, College Park, Maryland 20740.

Additional information about Merger Subsidiary 1 is included in documents incorporated by reference in this proxy statement/prospectus. See "Where You Can Find More Information" beginning on page [ ].

Merger Subsidiary 2

Merger Subsidiary 2, a direct wholly-owned subsidiary of IonQ, is a Delaware limited liability company organized on January 22, 2026 for the purpose of effecting the Second Merger. Merger Subsidiary 2 has not

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conducted any activities other than those incidental to its formation and the matters contemplated by the Merger Agreement, including the preparation of applicable regulatory filings in connection with the Transactions. The principal executive offices of Merger Subsidiary 2 are located at 4505 Campus Drive, College Park, Maryland 20740.

Additional information about Merger Subsidiary 2 is included in documents incorporated by reference in this proxy statement/prospectus. See "Where You Can Find More Information" beginning on page [ ].

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SKYWATER SPECIAL MEETING

This proxy statement/prospectus is being provided to the SkyWater stockholders as part of a solicitation of proxies by the SkyWater Board for use at the special meeting to be held at the time and place specified below and at any properly convened meeting following an adjournment or postponement thereof. This proxy statement/prospectus provides SkyWater stockholders with information they need to know to be able to vote or instruct their vote to be cast at the special meeting.

Date, Time and Place

The special meeting of SkyWater stockholders will be held virtually at www.virtualshareholdermeeting.com/SKYT2026SM, on [   ], 2026, at [ ]:[ ] [a.m./p.m.], Central Time. On or about [   ], 2026, SkyWater commenced mailing this proxy statement/prospectus and the enclosed form of proxy to its stockholders entitled to vote at the special meeting.

The special meeting can be accessed by visiting www.virtualshareholdermeeting.com/SKYT2026SM, where SkyWater stockholders will be able to participate and vote online. SkyWater encourages its stockholders to access the meeting prior to the start time leaving ample time for check-in. Please follow the instructions as outlined in this proxy statement/prospectus. This proxy statement/prospectus is first being furnished to SkyWater's stockholders on or about [   ], 2026.

SkyWater has chosen to hold the special meeting solely via live webcast and not in a physical location.

Purpose of the Special Meeting

At the special meeting, SkyWater stockholders will be asked to consider and vote on the following:

Recommendation of the SkyWater Board

At a special meeting held on January 25, 2026, the SkyWater Board unanimously determined that the Merger Agreement and the Transactions contemplated thereby, including the Mergers, are fair to and in the best interests of the SkyWater stockholders, approved and declared advisable the Merger Agreement and the Transactions contemplated thereby, including the Mergers, and directed that the Merger Agreement be submitted to the SkyWater stockholders for adoption at a meeting of such stockholders. The SkyWater Board unanimously recommends that SkyWater stockholders vote "FOR" the Merger Agreement proposal and "FOR" the adjournment proposal.

SkyWater stockholders should carefully read this proxy statement/prospectus, including any documents incorporated by reference, and the annexes in their entirety for more detailed information concerning the Mergers and the Transactions contemplated by the Merger Agreement.

Record Date; Stockholders Entitled to Vote

Only holders of record of SkyWater common stock at the close of business on [   ], 2026, the record date, will be entitled to notice of, and be able to vote at, the special meeting or any adjournment or postponement thereof.

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On the record date, there were [    ] shares of SkyWater common stock outstanding and entitled to vote at the special meeting. Each share of SkyWater common stock outstanding on the record date entitles the holder thereof to one vote on each proposal to be considered at the special meeting. SkyWater stockholders may vote virtually at the meeting or by proxy through the internet or by telephone or by a properly executed and delivered proxy card with respect to the special meeting.

A complete list of SkyWater stockholders of record who are entitled to vote at the special meeting will be available for inspection for a period of 10 days ending the day prior to the special meeting and during the special meeting at www.virtualshareholdermeeting.com/SKYT2026SM by entering the control number provided on your proxy card, voting instruction form or notice.

Voting by SkyWater's Directors and Executive Officers

At the close of business on [   ], 2026, the most recent practicable date for which such information was available, directors and executive officers of SkyWater and their respective affiliates owned and were entitled to vote [    ] shares of SkyWater common stock, representing approximately [  ]% of the shares of SkyWater common stock outstanding on that date. The number and percentage of shares of SkyWater common stock owned by directors and executive officers of SkyWater and their respective affiliates as of the record date are not expected to be meaningfully different from the number and percentage as of [   ], 2026. SkyWater currently expects all of its directors and executive officers to vote their shares of SkyWater common stock in favor of each of the proposals to be voted on at the special meeting but only Loren Unterseher, a member of the SkyWater Board, has entered into an agreement obligating him or her to do so. Pursuant to the Voting Agreement, Mr. Unterseher and his affiliates have agreed to vote in favor of adoption of the Merger Agreement and approval of the Mergers and the other Transactions contemplated by the Merger Agreement, subject to the terms and conditions of the voting agreement, as described under "The Merger Agreement-Summary of Voting Agreement" beginning on page [ ]. Mr. Unterseher and his affiliates owned and were entitled to vote [    ] shares of SkyWater common stock, representing approximately [  ]% of the shares of SkyWater common stock outstanding on [   ], 2026.

Quorum; Adjournment

The special meeting may be adjourned or postponed, in the absence of a quorum, by the chair of the meeting or the affirmative vote of holders of a majority of the shares of SkyWater common stock present in person or represented by proxy and entitled to vote at the special meeting. Even if a quorum is present, the special meeting may also be adjourned in order to provide more time to solicit additional proxies in favor of adoption of the Merger Agreement by the chair of the meeting or if sufficient votes are cast in favor of the adjournment proposal. If a sufficient number of shares of SkyWater common stock is present in person or represented by proxy and votes in favor of the Merger Agreement proposal at the special meeting such that the Merger Agreement proposal is approved, SkyWater does not anticipate that it will adjourn or postpone the special meeting.

Notice need not be given of the adjourned meeting if the time and place thereof are announced at the meeting at which the adjournment is taken unless:

At any adjourned meeting, all proxies will be voted in the same manner as they would have been voted at the original convening of the special meeting, except for any proxies that have been effectively revoked or withdrawn prior to the adjourned meeting. Any adjournment or postponement of the special meeting will allow SkyWater stockholders who have already submitted their proxies to revoke them at any time before their use at the special meeting that was adjourned or postponed.

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Abstentions will count as votes present and entitled to vote for the purpose of determining the presence of a quorum for the transaction of business at the special meeting. Broker non-votes will not be counted as present for the purpose of determining the presence of a quorum.

Required Vote; Broker Non-Votes and Abstentions

Each share of SkyWater common stock outstanding on the record date is entitled to one vote on each of the Merger Agreement proposal and the adjournment proposal. The required votes to approve the proposals at the special meeting are as follows:

Voting of Proxies by Holders of Record

How to Vote by Proxy if You are the Record Holder of Your Shares

If you were the record holder of your shares as of the record date, you may submit your proxy to vote by mail, by telephone or via the internet.

Voting via the Internet or by Telephone

Voting by Mail

As an alternative to submitting your proxy via the internet or by telephone, you may submit your proxy by mail.

How to Vote Your Shares if You are a "Street Name" Holder

If you hold your shares through a broker, bank or other nominee, also referred to as a "street name" holder, check the instructions provided by that entity to determine which options are available to you with respect to voting your shares.

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General

Please be aware that any costs related to voting via the internet, such as internet access charges, will be your responsibility.

All properly signed proxies that are timely received and that are not revoked will be voted at the special meeting according to the instructions indicated on the proxies or, if no direction is indicated, they will be voted as recommended by the SkyWater Board. The proxy holders may use their discretion to vote on other matters that properly come before the special meeting.

Attendance at the Special Meeting and Voting Virtually

The special meeting will be a completely virtual meeting. There will be no physical meeting location and the meeting will only be conducted via live webcast. The virtual special meeting will be held on [   ], 2026 at [ ]:[ ] [a.m./p.m.], Central Time. To participate in the special meeting and submit questions during the special meeting, visitwww.virtualshareholdermeeting.com/SKYT2026SM and enter the 16-digit control number on the proxy card or voting instruction form you received. Online check-in will begin at [ ]:[ ] [a.m./p.m.], Central Time. Please allow time for online check-in procedures.

The virtual stockholder meeting format uses technology designed to increase stockholder access, save SkyWater and SkyWater stockholders time and money, and provide SkyWater stockholders rights and opportunities to participate in the meeting similar to what they would have at an in-person meeting. In addition to online attendance, we will provide stockholders with an opportunity to hear all portions of the official meeting, submit written questions and comments during the meeting, and vote online during the open poll portion of the meeting.

Revocability of Proxies

Any stockholder giving a proxy has the power to revoke it at any time before the proxy is voted at the special meeting. If you are a stockholder of record, you may revoke your proxy in any of the following ways:

If you are a street name stockholder (for example, if your shares are held in the name of a bank, broker or other holder of record) and you vote by proxy, you may later revoke your proxy by informing the holder of record in accordance with that entity's procedures. You may also revoke your proxy by voting virtually at the special meeting.

Solicitation

The SkyWater Board is soliciting proxies for the special meeting from its stockholders. SkyWater will pay all costs it incurs in the solicitation of proxies, except that IonQ has agreed to pay the costs and expenses of printing, mailing and filing this proxy statement/prospectus. Proxies may be solicited by directors, officers and a small number of SkyWater's regular employees personally or by mail, telephone or facsimile, but such persons will not be specially compensated for such service. SkyWater has retained Innisfree M&A Incorporated, a proxy

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solicitation firm, to assist in the solicitation of proxies for an estimated fee of approximately $30,000 plus a 50% success fee conditioned on success with the SkyWater Stockholder Approval as well as reasonable out-of-pocket costs and expenses for the services of the firm. As appropriate, copies of solicitation material will be furnished to brokerage houses, fiduciaries and custodians that hold shares of SkyWater common stock of record for beneficial owners for forwarding to such beneficial owners. SkyWater may also reimburse persons representing beneficial owners for their costs of forwarding the solicitation material to such owners.

Assistance

If you need assistance with voting via the internet, voting by telephone or completing your proxy card, or have questions regarding the special meeting, please contact SkyWater's proxy solicitor at the following telephone number:

Innisfree M&A Incorporated

Shareholders, please call toll-free: +1 (888) 750-5835 (U.S. and Canada)

               +1 (412) 232-3651 (all other countries)

Banks and brokerage firms may call: +1 (212) 750-5833 (collect)

Your vote is very important regardless of the number of shares of SkyWater common stock that you own. Please submit a proxy to vote your shares via the internet, vote by telephone or sign, date and return a proxy card promptly so your shares can be represented, even if you plan to attend the special meeting.

Tabulation of Votes

Representatives of Broadridge will tabulate the votes cast at the special meeting and act as the Independent Inspector of Election.

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SKYWATER PROPOSALS

Item 1. The Merger Agreement Proposal

(Item 1 on SkyWater Proxy Card)

In the Merger Agreement proposal, SkyWater is asking its stockholders to adopt the Merger Agreement. Approval of the Merger Agreement proposal by SkyWater stockholders is required for completion of the Mergers. The Merger Agreement proposal requires the affirmative vote of holders of a majority of the outstanding shares of SkyWater common stock entitled to vote thereon. Each share of SkyWater common stock outstanding on the record date of the special meeting is entitled to one vote on this proposal. Failures to vote, broker non-votes and abstentions will have the same effect as votes cast "AGAINST" this proposal.

The SkyWater Board unanimously recommends a vote "FOR" the Merger Agreement proposal (Item 1).

Item 2. The Adjournment Proposal

(Item 2 on SkyWater Proxy Card)

In the adjournment proposal, SkyWater is asking its stockholders to approve the adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes to adopt the Merger Agreement. If SkyWater stockholders approve the adjournment proposal, subject to the terms of the Merger Agreement, SkyWater could adjourn the special meeting and use the additional time to solicit additional proxies, including soliciting proxies from SkyWater stockholders who have previously voted. SkyWater does not intend to call a vote on the adjournment proposal if the Merger Agreement proposal is approved at the special meeting.

The adjournment proposal requires the affirmative vote of holders of a majority of the outstanding shares of SkyWater common stock present in person or represented by proxy at the special meeting and entitled to vote thereon. Failures to be present virtually or by proxy, including broker non-votes, will have no effect on the vote for this proposal (assuming a quorum is present). Abstentions will have the same effect as votes cast "AGAINST" this proposal.

The SkyWater Board unanimously recommends a vote "FOR" the adjournment proposal (Item 2).

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COMPARATIVE PER SHARE MARKET PRICE DATA AND DIVIDENDS

IonQ common stock is listed on the New York Stock Exchange under the symbol "IONQ," and SkyWater common stock is listed on the Nasdaq Capital Market under the symbol "SKYT." The following table sets forth the closing sale prices per share of IonQ common stock and SkyWater common stock on (i) January 23, 2026, the last full trading day prior to the public announcement of the execution of the Merger Agreement, and (ii) [  ], 2026, the last practicable trading day before the date of this proxy statement/prospectus. The table also shows, for each date, the assumed Exchange Ratio and the implied value of the Per Share Stock Consideration and of the total Merger Consideration per share of SkyWater common stock, in each case calculated for illustrative purposes only. The assumed Exchange Ratio for each date below reflects the quotient of $20.00 divided by the closing price of IonQ common stock on such date, subject to the collar described under "The Merger Agreement-Merger Consideration" and does not reflect the 20-trading-day volume-weighted average price methodology actually used to determine the Exchange Ratio.

The market prices (and 20-Day VWAPs) of IonQ common stock and SkyWater common stock have fluctuated since the announcement of execution of the Merger Agreements and may continue to fluctuate before the completion of the Mergers and, with respect to IonQ common stock, thereafter. Accordingly, these comparisons may not provide meaningful information to stockholders in determining how to vote on the proposals described in this proxy statement/prospectus. You are urged to obtain current market quotations for IonQ common stock and SkyWater common stock.

Dividends

Neither IonQ nor SkyWater has ever paid a cash dividend on its common stock. The Merger Agreement limits the ability of SkyWater to declare or pay dividends prior to completion of the Mergers, without the consent of the other party. Any determination to pay dividends after completion of the Mergers will be made by IonQ's board of directors, in its discretion, and will depend upon IonQ's results of operations, financial condition, capital requirements, contractual restrictions, business prospects and other factors that the IonQ board of directors deems relevant. Stockholders have no contractual right to dividends that have not been declared.

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DESCRIPTION OF IONQ CAPITAL STOCK

The following describes the material terms of the capital stock of IonQ. This description is qualified in its entirety by reference to IonQ's Certificate of Incorporation and IonQ's Bylaws which are incorporated by reference into this proxy statement/prospectus. For more information about the documents incorporated by reference into this proxy statement/prospectus, see "Where You Can Find More Information" on page [ ].

The authorized capital stock of IonQ currently consists of one billion shares of common stock, par value $0.0001 per share, and 20 million shares of preferred stock, par value $0.0001 per share.

IonQ Common Stock

Except as otherwise required by law or as otherwise provided in any certificate of designation for any series of preferred stock, holders of IonQ common stock possess all voting power for the election of IonQ's directors and all other matters requiring stockholder action. Holders of IonQ common stock are entitled to one vote per share on matters to be voted on by stockholders.

Subject to preferences that may apply to any then-outstanding preferred stock, the holders of common stock may be entitled to receive dividends out of legally available funds if the IonQ Board, in its discretion, determines to issue dividends and then only at the times and in the amounts that the IonQ Board may determine. IonQ does not anticipate paying any cash dividends in the foreseeable future.

In the event of IonQ's voluntary or involuntary liquidation, dissolution, distribution of assets or winding-up, the holders of common stock will be entitled to receive an equal amount per share of all of IonQ's assets of whatever kind available for distribution to stockholders, after the rights of the holders of the preferred stock, if any, have been satisfied.

IonQ's stockholders have no preemptive or other subscription rights and there are no sinking fund or redemption provisions applicable to IonQ common stock.

IonQ Preferred Stock

Under IonQ's Certificate of Incorporation, the IonQ Board may, without further action by IonQ's stockholders, fix the rights, preferences, privileges and restrictions of up to an aggregate of 20,000,000 shares of preferred stock in one or more series and authorize their issuance. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences and the number of shares constituting any series or the designation of such series, any or all of which may be greater than the rights of common stock. Any issuance of preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders would receive dividend payments and payments on liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deterring or preventing a change of control or other corporate action. IonQ has no present plans to issue any shares of preferred stock.

Transfers

IonQ shall have power to enter into and perform any agreement with any number of stockholders of any one or more classes or series of stock of IonQ to restrict the transfer of shares of stock of IonQ of any one or more classes or series owned by such stockholders in any manner not prohibited by the DGCL.

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Anti-Takeover Provisions

Section 203 of the DGCL

IonQ is subject to Section 203 of the DGCL, which prohibits a publicly held Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years after the date that such stockholder became an interested stockholder, with the following exceptions:

In general, Section 203 defines a "business combination" to include the following:

In general, Section 203 defines an "interested stockholder" as an entity or person who, together with the person's affiliates and associates, beneficially owns or within three years prior to the time of determination of interested stockholder status did own, 15% or more of the outstanding voting stock of the corporation.

A Delaware corporation may "opt out" of these provisions with an express provision in its original certificate of incorporation or an express provision in its amended and restated certificate of incorporation or amended and restated bylaws resulting from a stockholders' amendment approved by at least a majority of the outstanding voting shares. IonQ has not opted out of these provisions. As a result, mergers or other takeover or change in control attempts of IonQ may be discouraged or prevented.

Certificate of Incorporation and Bylaws

Among other things, IonQ's Certificate of Incorporation and IonQ's Bylaws:

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provide that, subject to the rights of any series of preferred stock to elect directors, directors may only be removed with cause, which removal may be effected, subject to any limitation imposed by law, by the holders of at least 66 2/3% of the voting power of all of IonQ's then-outstanding shares of the capital stock entitled to vote generally at an election of directors;

provide that all vacancies, including newly created directorships, may, except as otherwise required by law, be filled by the affirmative vote of a majority of directors then in office, even if less than a quorum;

require that any action to be taken by IonQ's stockholders must be effected at a duly called annual or special meeting of stockholders and not be taken by written consent or electronic transmission;

provide that stockholders seeking to present proposals before a meeting of stockholders or to nominate candidates for election as directors at a meeting of stockholders must provide advance notice in writing, and also specify requirements as to the form and content of a stockholder's notice;

provide that special meetings of IonQ's stockholders may be called by the chairperson of the IonQ Board, IonQ's Chief Executive Officer, or by the IonQ Board pursuant to a resolution adopted by the majority of the IonQ Board; and

not provide for cumulative voting rights, therefore allowing the holders of a majority of the shares of common stock entitled to vote in any election of directors to elect all of the directors standing for election, if they should so choose.

The amendment of any of these provisions would require approval by the holders of at least 66 2/3% of the voting power of all of IonQ's then-outstanding capital stock entitled to vote generally in the election of directors, voting together as a single class.

The combination of these provisions will make it more difficult for IonQ's existing stockholders to replace the IonQ Board as well as for another party to obtain control of IonQ by replacing the IonQ Board. Since the IonQ Board has the power to retain and discharge IonQ's officers, these provisions could also make it more difficult for existing stockholders or another party to effect a change in management. In addition, the authorization of undesignated preferred stock makes it possible for the IonQ Board to issue preferred stock with voting or other rights or preferences that could impede the success of any attempt to change IonQ's control.

These provisions are intended to enhance the likelihood of continued stability in the composition of the IonQ Board and its policies and to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to reduce IonQ's vulnerability to hostile takeovers and to discourage certain tactics that may be used in proxy fights. However, such provisions could have the effect of discouraging others from making tender offers for IonQ's shares and may have the effect of delaying changes in IonQ's control or management. As a consequence, these provisions may also inhibit fluctuations in the market price of IonQ's stock.

IonQ's Certificate of Incorporation provides that the Court of Chancery of the State of Delaware will be the exclusive forum for actions or proceedings brought under Delaware statutory or common law: (1) any derivative action or proceeding brought on IonQ's behalf; (2) any action asserting a breach of fiduciary duty owed by any of IonQ's current or former directors, officers or stockholders, to IonQ or IonQ's stockholders; (3) any action asserting a claim against IonQ arising under the DGCL; (4) any action regarding IonQ's Certificate of Incorporation or IonQ's Bylaws (as either may be amended from time to time); (5) any action as to which the Delaware General Corporate Law confers jurisdiction to the Court of Chancery of the State of Delaware; (6) any action asserting a claim against IonQ that is governed by the internal affairs doctrine, in all cases to the fullest extent permitted by law and subject to the court having personal jurisdiction over the indispensable parties named as defendants. IonQ's Certificate of Incorporation further provides that the federal district courts of the United States of America will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act.

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Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder. As a result, the exclusive forum provision of IonQ's Certificate of Incorporation will not apply to suits brought to enforce any duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction.

Although IonQ believes this provision benefits IonQ by providing increased consistency in the application of Delaware law in the types of lawsuits to which it applies, a court may determine that this provision is unenforceable, and to the extent it is enforceable, the provision may have the effect of discouraging lawsuits against IonQ's directors and officers, although IonQ's stockholders will not be deemed to have waived IonQ's compliance with federal securities laws and the rules and regulations thereunder and therefore bring a claim in another appropriate forum. Additionally, IonQ cannot be certain that a court will decide that this provision is either applicable or enforceable, and if a court were to find the choice of forum provision contained in IonQ's Certificate of Incorporation to be inapplicable or unenforceable in an action, IonQ may incur additional costs associated with resolving such action in other jurisdictions, which could harm IonQ's business, operating results and financial condition.

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COMPARISON OF RIGHTS OF STOCKHOLDERS OF IONQ AND SKYWATER

Both IonQ and SkyWater are incorporated under the laws of the State of Delaware and, accordingly, the rights of the stockholders of each are governed by the DGCL. IonQ will continue to be a Delaware corporation following completion of the Mergers and will be governed by the DGCL.

Upon completion of the Mergers, the SkyWater stockholders immediately prior to the Effective Time will become IonQ common stockholders. The rights of the former SkyWater stockholders and IonQ stockholders will thereafter be governed by the DGCL and by IonQ's Certificate of Incorporation and IonQ's Bylaws.

The following description summarizes certain of the material terms and differences between the rights of the stockholders of IonQ and SkyWater, but is not a complete statement of all such terms or differences, or a complete description of the specific provisions referred to in this summary. Stockholders should read carefully the relevant provisions of the DGCL and the respective certificates of incorporation and bylaws of IonQ and SkyWater. For more information on how to obtain the documents that are not attached to this proxy statement/prospectus, see "Where You Can Find More Information" beginning on page [   ].

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VALIDITY OF COMMON STOCK

The validity of IonQ common stock to be issued in the Mergers will be passed upon for IonQ by Paul, Weiss, Rifkind, Wharton & Garrison LLP.

STOCKHOLDER PROPOSALS AND NOMINATIONS FOR SKYWATER'S 2027 ANNUAL MEETING OF STOCKHOLDERS

If the Mergers are completed in 2026, SkyWater will become a direct, wholly-owned subsidiary of IonQ and, consequently, will not hold an annual meeting of its stockholders in 2027. If the Merger Agreement is not adopted by the requisite vote of the SkyWater stockholders or if the Mergers are not completed for any other reason, SkyWater intends to hold an annual meeting of its stockholders in 2027 (the "SkyWater 2027 Annual Meeting").

A stockholder who intends to present a proposal for action at the SkyWater 2027 Annual Meeting and who desires that such proposal be included in SkyWater's proxy materials pursuant to SEC Rule 14a-8 must submit the proposal to SkyWater at its principal executive offices at 2401 East 86th Street Bloomington, Minnesota 55425, directed to the attention of its Secretary, no later than [ ], 2026.

A stockholder who otherwise intends to present business, other than a stockholder proposal pursuant to Rule 14a-8, or to nominate a director at the SkyWater 2027 Annual Meeting must comply with the requirements set forth in SkyWater's Bylaws. Among other matters, a stockholder must give written notice containing the information specified in SkyWater's Bylaws to its Secretary at SkyWater's principal executive offices not later than 5:00 PM Eastern Time on the 90th day nor earlier than the 120th day prior to the first anniversary of the preceding year's annual meeting. Under SkyWater's Bylaws, SkyWater must receive notice of a stockholder's intent to present business, other than pursuant to Rule 14a-8, or to nominate a director at the SkyWater 2027 Annual Meeting no later than 5:00 PM Eastern Time on [   ], 2027 and no earlier than [   ], 2027. If the notice is received outside of that time frame, then SkyWater is not required to permit the business or the nomination to be presented at the SkyWater 2027 Annual Meeting. Nevertheless, if the SkyWater Board chooses to present such proposal at the SkyWater 2027 Annual Meeting, then the persons named in proxies solicited by the SkyWater Board for the SkyWater 2027 Annual Meeting may exercise discretionary voting power with respect to such proposal. In addition to satisfying the foregoing requirements under SkyWater's Bylaws, stockholders who intend to solicit proxies in support of director nominees other than the SkyWater's nominees must provide notice that sets forth the information required by Rule 14a-19(b) under the Exchange Act of 1934.

EXPERTS

The consolidated financial statements of IonQ, Inc. appearing in IonQ, Inc.'s Annual Report (Form 10-K) for the year ended December 31, 2025, and the effectiveness of IonQ, Inc.'s internal control over financial reporting as of December 31, 2025 (excluding the internal control over financial reporting of id Quantique SA, Capella Space Corp., Oxford Ionics Limited, and Vector Atomic Inc.), have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, which as to the report on the effectiveness of IonQ, Inc.'s internal control over financial reporting contains an explanatory paragraph describing the above referenced exclusion of id Quantique SA, Capella Space Corp., Oxford Ionics Limited, and Vector Atomic Inc. from the scope of such firm's audit of internal control over financial reporting, included therein, and incorporated herein by reference. Such financial statements have been incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

The consolidated financial statements of SkyWater Technology, Inc. and subsidiaries as of December 28, 2025, and December 29, 2024, and for each of the years in the two-year period ended December 28, 2025, have been incorporated by reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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HOUSEHOLDING OF PROXY STATEMENT/PROSPECTUS

The SEC has adopted rules that permit companies and intermediaries such as brokers to satisfy delivery requirements for proxy statements and annual reports with respect to two or more stockholders sharing the same address by delivering a single proxy statement or annual report, as applicable, addressed to those stockholders. As permitted by the Exchange Act, only one copy of this proxy statement/prospectus is being delivered to stockholders residing at the same address, unless stockholders have notified SkyWater of their desire to receive multiple copies of this proxy statement/prospectus. This process, which is commonly referred to as "householding," potentially provides extra convenience for stockholders and cost savings for companies. If, at any time, you no longer wish to participate in householding and would prefer to receive a separate proxy statement/prospectus, or if you are receiving multiple copies of this proxy statement/prospectus and wish to receive only one, please contact SkyWater at its address identified below. SkyWater will promptly deliver, upon oral or written request, a separate copy of this proxy statement/prospectus to any stockholder residing at an address to which only one copy was mailed. Oral or written requests for additional copies should be directed to SkyWater at its phone number or address appearing on the cover of this proxy statement/prospectus, to the attention of the Secretary of SkyWater.

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WHERE YOU CAN FIND MORE INFORMATION

IonQ and SkyWater file annual, quarterly and current reports, proxy statements and other information with the SEC. You may access this information at the SEC's internet website that contains reports, proxy statements and other information regarding issuers, including IonQ and SkyWater, who file electronically with the SEC. The address of that site is www.sec.gov. The information contained on the SEC's website is expressly not incorporated by reference into this proxy statement/prospectus.

IonQ has filed with the SEC a registration statement on Form S-4 of which this proxy statement/prospectus forms a part. The registration statement registers the shares of IonQ common stock to be issued to SkyWater stockholders in connection with the Mergers. The registration statement, including the attached exhibits and annexes, contains additional relevant information about IonQ and SkyWater, respectively. The rules and regulations of the SEC allow IonQ and SkyWater to omit certain information included in the registration statement from this proxy statement/prospectus.

In addition, the SEC allows IonQ and SkyWater to disclose important information to you by referring you to other documents filed separately with the SEC. This information is considered to be a part of this proxy statement/prospectus, except for any information that is superseded by information included directly in this proxy statement/prospectus or incorporated by reference subsequent to the date of this proxy statement/prospectus as described below.

This proxy statement/prospectus incorporates by reference the documents listed below that IonQ and SkyWater have previously filed with the SEC. They contain important information about the companies and their financial condition.

IonQ SEC Filings

SkyWater SEC Filings

To the extent that any information contained in any report on Form 8-K, or any exhibit thereto, was furnished to, rather than filed with, the SEC, such information or exhibit is specifically not incorporated by reference.

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In addition, IonQ and SkyWater incorporate by reference any future filings they make with the SEC under Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act after the date of this proxy statement/prospectus and before the date of the special meeting (excluding any current reports on Form 8-K, or portions of current reports on Form 8-K, to the extent disclosure is furnished and not filed). Those documents are considered to be a part of this proxy statement/prospectus, effective as of the date they are filed. In the event of conflicting information in these documents, the information in the latest filed document should be considered correct.

You can obtain any of the other documents listed above from the SEC, through the SEC's website at the address indicated above, or from IonQ or SkyWater, as applicable, by requesting them in writing or by telephone as follows:

These documents are available from IonQ or SkyWater, as the case may be, without charge, excluding any exhibits to them unless the exhibit is specifically listed as an exhibit to the registration statement of which this proxy statement/prospectus forms a part. You can also find information about IonQ and SkyWater at their internet websites at www. IonQ.com and www.skywatertechnology.com, respectively. Information contained on these websites does not constitute part of this proxy statement/prospectus.

You may also obtain documents incorporated by reference into this document by requesting them by telephone from Innisfree M&A Incorporated, SkyWater's proxy solicitor, at the following telephone number:

Innisfree M&A Incorporated

Shareholders, please call toll-free: +1 (888) 750-5835 (U.S. and Canada)

                +1 (412) 232-3651 (all other countries)

Banks and brokerage firms may call: +1 (212) 750-5833 (collect)

If you are a stockholder of SkyWater and would like to request documents, please do so by [   ], 2026, which is five business days before the special meeting, to receive them before the meeting. If you request any documents from IonQ or SkyWater, IonQ or SkyWater, as applicable, will mail them to you by first class mail, or another equally prompt means, within one business day after IonQ or SkyWater, as the case may be, receives your request.

This proxy statement/prospectus is a prospectus of IonQ and a proxy statement of SkyWater for the special meeting. Neither IonQ nor SkyWater has authorized anyone to give any information or make any representation about the Mergers or IonQ or SkyWater that is different from, or in addition to, that contained in this proxy statement/prospectus or in any of the materials that IonQ or SkyWater has incorporated by reference into this proxy statement/prospectus. Therefore, if anyone does give you information of this sort, you should not rely on it. If you are in a jurisdiction where offers to exchange or sell, or solicitations of offers to exchange or purchase, the securities offered by this document or the solicitation of proxies is unlawful, or if you are a person to whom it is unlawful to direct these types of activities, then the offer presented in this document does not extend to you. This proxy statement/prospectus is dated [   ], 2026. You should not assume that the information is accurate as of any date other than that date, and neither its mailing to SkyWater stockholders nor the issuance of shares of IonQ common stock in the Mergers will create any implication to the contrary.

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Annex A

AGREEMENT AND PLAN OF MERGER

dated as of

January 25, 2026

among

IONQ, INC.,

IRIS MERGER SUBSIDIARY 1 INC.,

IRIS MERGER SUBSIDIARY 2 LLC

and

SKYWATER TECHNOLOGY, INC.

TABLE OF CONTENTS

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