Additional Proxy Soliciting Materials (Form DEFA14A)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

Janus Investment Fund

(Name of Registrant as Specified in Its Charters)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

To Our Valued Clients,

As you may have seen, Victory Capital has withdrawn its acquisition proposal. Thank you for your support and patience during the past few weeks.

Looking ahead, we remain incredibly excited to be moving forward with Trian and General Catalyst on our take-private transaction. In partnership with them both, we will be able to further invest in our product offering, client services, talent, and technology to accelerate our growth and build for the future.

We have remained fully focused on completing the steps to close the transaction as quickly as possible. Essential to completing the transaction is obtaining the required client consents. This process is underway, and we encourage you to provide your consent on the Trian/General Catalyst transaction promptly when your formal solicitation is received. If you have any questions about the consent process, please don't hesitate to contact your Janus Henderson representative.

As we move forward, we remain on track to complete the Trian/General Catalyst transaction in mid-2026.

We are tremendously honored to serve you and will continue to put our clients first-always. We look forward to investing in a brighter future together with you.

Thank you for the trust you have placed in Janus Henderson Investors.

Regards,

Janus Henderson Investors

Forward Looking Statements

References to the "Funds" herein refer to the U.S. registered investment companies managed by Janus Henderson Investors U.S. LLC and references herein to "Janus Henderson" refer to Janus Henderson Group plc and its affiliates. Certain statements in this communication not based on historical facts are "forward-looking statements" within the meaning of the federal securities laws. Such forward-looking statements involve known and unknown risks and uncertainties that are difficult to predict and could cause our actual results, performance or achievements to differ materially from those discussed. These include statements as to Janus Henderson's and the Funds' future expectations, beliefs, plans, strategies, objectives, events, conditions, financial performance, prospects or future events, including with respect to the timing and anticipated benefits of pending and recently completed transactions and strategic partnerships, and expectations regarding opportunities that align with our strategy. In some cases, forward-looking statements can be identified by the use of words such as "may," "could,"

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"expect," "intend," "plan," "seek," "anticipate," "believe," "estimate," "predict," "potential," "continue," "likely," "will," "would," and similar words and phrases. Forward-looking statements are necessarily based on estimates and assumptions that, while considered reasonable by, as applicable, Janus Henderson and the Funds and their respective management, are inherently uncertain. Accordingly, you should not place undue reliance on forward-looking statements, which speak only as of the date they are made and are not guarantees of future performance. Neither Janus Henderson nor the Funds undertake any obligation to publicly update or revise these forward-looking statements.

Various risks, uncertainties, assumptions and factors that could cause Janus Henderson's or the Funds' future results to differ materially from those expressed by the forward-looking statements included in this communication include, but are not limited to, the impact of any alternative proposal, Janus Henderson's and the Funds' ability to obtain the applicable regulatory, shareholder and other approvals required to consummate the proposed transaction and the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction would not occur, the outcome of any legal proceedings that may be instituted against the parties and others related to the proposed transaction, that shareholder litigation in connection with the proposed transaction may affect the timing or occurrence of the proposed transaction or result in significant costs of defense, indemnification and liability, unanticipated difficulties or expenditures relating to the proposed transaction, including the impact of the transaction on Janus Henderson's or the Funds' business, that the proposed transaction generally may involve unexpected costs, liabilities or delays, that the business of Janus Henderson or the Funds may suffer as a result of uncertainty surrounding the proposed transaction or the identity of the purchaser, that Janus Henderson or the Funds may be adversely affected by other economic, business, and/or competitive factors, including the net asset value of assets in the Funds or certain other of Janus Henderson's funds, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction, changes in interest rates and inflation, changes in trade policies (including the imposition of new or increased tariffs), volatility or disruption in financial markets, Janus Henderson's investment performance as compared to third-party benchmarks or competitive products, redemptions, and other risks, uncertainties, assumptions, and, with respect to Janus Henderson, factors discussed in Janus Henderson's Annual Report on Form 10-K for the year ended December 31, 2025, and in other filings or furnishings made by Janus Henderson with the SEC from time to time and, in respect of the Funds, factors discussed in each Funds' current prospectus.

Important Additional Information and Where to Find It

In connection with the proposed transaction, Janus Henderson filed a definitive proxy statement with the U.S. Securities and Exchange Commission (the "SEC") on March 11, 2026, which was first mailed to Janus Henderson's shareholders on or about March 12, 2026 and the Funds filed definitive proxy statements with the SEC on March 2, 2026, which will be sent or provided to Fund shareholders. Janus Henderson and affiliates of Janus Henderson jointly filed a transaction statement on Schedule 13E-3 on March 11, 2026. Janus Henderson and the Funds may also file other documents with the SEC regarding the proposed transaction, including amendments to the proxy statement or Schedule 13E-3. This communication is not a substitute for any proxy statement, the Schedule 13E-3 or any other document that may be filed by Janus Henderson or the Funds with the SEC. INVESTORS AND SECURITY HOLDERS OF JANUS HENDERSON AND THE FUNDS ARE URGED TO READ THE APPLICABLE PROXY STATEMENT, THE SCHEDULE 13E-3 (AS APPLICABLE) AND ANY OTHER RELEVANT

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DOCUMENTS FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY, BECAUSE THEY CONTAIN OR WILL CONTAIN IMPORTANT INFORMATION. Investors and security holders will be able to obtain the proxy statement and the Schedule 13E-3 (in each case, when available) and other documents that are filed with the SEC by Janus Henderson and the Funds free of charge from the SEC's website at https://www.sec.gov or, with respect to Janus Henderson, through the investor relations section of Janus Henderson's website at https://ir.janushenderson.com.

Participants in the Solicitation

With respect to Janus Henderson, Janus Henderson and its directors and certain of its executive officers and other employees may be deemed to be participants in the solicitation of proxies from Janus Henderson's shareholders in connection with the proposed transaction. With respect to the Funds, the Funds and its manager and its and their directors and certain of its executive officers and other employees may be deemed to be participants in the solicitation of proxies from Janus Henderson's shareholders in connection with the proposed transaction. Information about the directors and executive officers of Janus Henderson and their ownership of Janus Henderson common shares is contained in the definitive proxy statement for Janus Henderson's 2025 annual meeting of shareholders (the "Annual Meeting Proxy Statement"), which was filed with the SEC on March 21, 2025, including under the headings "Proposal 1: Election of Directors," "Corporate Governance," "Board Compensation," "Proposal 2: Advisory Say-on-Pay Vote on Executive Compensation," "Executive Compensation," "Executive Compensation Tables," "Securities Ownership of Certain Beneficial Owners and Management" and "Our Executive Officers." Information about the trustees and executive officers of the Funds and their ownership of the Funds is contained in each Fund's current statement of additional information. Additional information regarding the persons who may, under the rules of the SEC, be deemed participants in the solicitation of the shareholders of Janus Henderson or the Funds, as applicable, in connection with the proposed transaction, including a description of their direct or indirect interests, by security holdings or otherwise, are included in the Funds' proxy statements filed with the SEC. To the extent holdings of securities by potential participants (or the identity of such participants) have changed since the information printed in the Janus Henderson Annual Meeting Proxy Statement, such information has been or will be reflected on the Statements of Change in Ownership of Janus Henderson on Forms 3 and 4 filed with the SEC. The Funds are not subject to Form 3 and 4 filings. Free copies of the proxy statement relating to the proposed transaction and free copies of the other SEC filings to which reference is made in this paragraph may be obtained from the SEC's website at https://www.sec.gov or, with respect to Janus Henderson, through the investor relations section of Janus Henderson's website at https://ir.janushenderson.com.

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Opening Key Phrase

Thank you for calling the Janus Henderson Proxy Event line. My name is (name); may I have your name please?

[Wait for response and notate the last name]

Thank you, Mr./ Mrs. (name), are you calling in reference to a communication that you received regarding the current proxy vote?

[If yes, verify which communication they received]

Yes, that is from our partners at Alliance Advisors informing you of your right to vote on this proxy. How may I help you today?

[If caller wishes to vote]

I can review your options for voting, or connect you with our Proxy partner, Alliance Advisors to vote now if you would like?

[If no]

We are a team dedicated to answering proxy-related questions, however, if you have account specific questions I can transfer you to an account specialist to assist further if you would like?

Closing Key Phrase

Thank you for reaching out regarding this process, are there any other questions about the Proxy Event that I can answer for you at this time?

If you find you have any additional questions Mr./ Mrs. (name), the phone center is open Monday through Friday from 9:00 A.M. to 6:00 P.M. eastern time. Information about the Proxy can be found on our website at www.votejhi.com/mutualfunds.

Janus Henderson appreciates your business and participation in this proxy, thank you for calling and have a nice day.

SCRIPT QUESTION AND ANSWERS - FOR INTERNAL USE ONLY

On December 21, 2025, Janus Henderson entered into an agreement, pursuant to which an investor group, led by Trian and General Catalyst, will take the firm private. Shareholders of the Janus Henderson funds are not being asked to vote on the transaction. Rather, shareholders of each fund are being asked to vote on a proposal to approve a new investment advisory agreement that is being presented to them as a result of the proposed transaction.

Although following the completion of the transaction the business will be run substantially the same, the closing of the transaction constitutes a change of control of Janus Henderson Investors US LLC (the "Adviser"), which under the 1940 Act is deemed to be an "assignment" of the funds' investment advisory agreements with the Adviser, which will cause the agreements to terminate.

To enable Janus Henderson to continue to serve as your fund's investment adviser upon the closing of the transaction, as Janus Henderson would be under new "parent" ownership, the Board of Trustees recommends that you vote FOR approval of the new investment advisory agreement between your fund and Janus Henderson Investors.

The following are general rules for signing proxy cards:

As a result of the transaction, your fund investment will not change. You will still own the same fund shares and the underlying value of those shares is not expected to change as result of the transaction. Your fund will continue to be managed by the same investment team and in accordance with the existing investment objectives and policies. There will be no change to the advisory fee rate as a result of the transaction. The terms of the new advisory agreements for funds are substantially identical to those of their current advisory agreements.

PROPOSAL TO APPROVE NEW INVESTMENT ADVISORY AGREEMENTS

Janus Henderson Investors currently serves as your fund's investment adviser. The closing of the transaction is considered an "assignment" of the current investment advisory agreement with your fund. As is industry standard based on SEC rules, the terms of the current investment advisory agreement state that an assignment of such agreement causes the agreement to automatically terminate.

To enable Janus Henderson to continue to serve as your fund's investment adviser upon the closing of the transaction, we must request shareholder approval of a new investment advisory agreement between Janus Henderson Investors and your fund. The Board recommends that shareholders vote FOR approval of the new investment advisory agreement for each fund.

No. The terms of your fund's new investment advisory agreement with the Adviser are substantially identical to the current investment advisory agreement. There will be no change in the contractual advisory fee rate your fund pays or the investment advisory services it receives as a result of the transaction.

Subject to 1940 Act restrictions, if your fund does not receive the required shareholder approval, Janus Henderson may continue to manage your fund under an interim investment advisory agreement for the earlier of 150 days after the completion of the transaction or until shareholders approve the new investment advisory agreement. The Board urges you to vote without delay.

MUTUAL FUND SHAREHOLDERS ONLY:PROPOSAL TO ELECT TRUSTEES

You are being asked to elect eight Trustees to serve on the Board: Cheryl D. Alston, Alan A. Brown, Raudline Etienne, Darrell B. Jackson, Dominic Janssens, William F. McCalpin, Gary A Poliner, and Gwen L. Shaneyfelt. All nominees, other than Gwen L. Shaneyfelt, are currently Trustees of the Trust and have served in that capacity since originally elected or appointed. Ms. Shaneyfelt was unanimously approved by the Board to stand for election, upon a recommendation from the Trust's Nominating and Governance Committee. Each of the current Trustees and Ms. Shaneyfelt are considered "independent," meaning that the Trustees and nominees are not affiliated with Janus Henderson Investors US LLC ("Janus Henderson Investors"), the funds' adviser, or its related entities (an "Independent Trustee").

You are being asked to elect Ms. Shaneyfelt and each currently serving Trustee as Independent Trustees to (1) return the Board to its normal size of eight trustees and (2) provide the Board with flexibility going forward to appoint Trustees to fill vacancies as needed without the time and expense of unnecessary proxy solicitations.

No, the election of the Trustees is not related to the transaction.

VOTING PROCEDURES

Shareholders who owned shares of a fund at the close of business on Thursday, February 12, 2026 (the "Record Date") are eligible to vote. Those shareholders are entitled to one vote for each whole dollar (and a proportionate fractional vote for each fractional dollar) of net asset value owned on all matters presented at the Meeting regarding their fund.

The Special Meeting of Shareholders will be held on Monday, May 18, 2026, in a virtual meeting format, which will be conducted via live webcast. You may attend the Special Meeting of Shareholders online, vote your shares electronically and submit questions by visiting https://web.viewproxy.com/janushendersonjifjas/2026.

You can vote in any one of five ways:

Yes. You may revoke your proxy vote at any time before it is voted at the Meeting by: (i) delivering a written revocation to the Secretary of the Trust at 151 Detroit Street, Denver, Colorado 80206;

(ii) submitting a subsequently executed proxy vote; or (iii) attending the Meeting virtually and voting online. Even if you plan to attend the Meeting, we ask that you return your proxy. This will help us ensure that an adequate number of shares are present at the Meeting for consideration of the proposals.

Approval of the proposal to approve your fund's new investment advisory agreement requires the vote of a "majority of the outstanding voting securities" of your fund as defined under the 1940 Act ("1940 Act Majority"). A 1940 Act Majority means the vote of the lesser of (i) 67% of the fund entitled to vote present, if the holders of more than 50% of such outstanding shares are present; or (ii) more than 50% of such outstanding shares of the fund entitled to vote.

Shareholders of each fund will vote separately on the new investment advisory agreements relating to their fund. An unfavorable vote on any proposal by the shareholders of one fund will not affect another fund if the proposal is approved by the shareholders of that fund. However, the new investment advisory agreements will only take effect upon the closing of the transaction, which is conditioned upon, among other things, obtaining the approval of new investment advisory agreements by Janus Henderson's advisory clients representing a specified percentage of Janus Henderson's assets under management.

For Mutual Fund Shareholders Only: For the Proposal to Elect Trustees, the Trustee elections will be determined by a plurality vote (the greatest number of votes) of the shares of all funds. A quorum of shareholders is required to take action at the Meeting. The presence of 30% of shares outstanding and entitled to vote at the Meeting constitutes a quorum.

The new investment advisory agreement between Janus Henderson Investors and your fund is contingent upon the closing of the transaction and, if approved, will only take effect if the transaction closes.

Alliance will only have access to the following shareholder data (for direct and beneficial "NOBO" holders):

Clients can call Alliance Advisors, the proxy solicitor engaged by the funds, toll-free at:

Clients can also visit:

If you received a Notice of Internet Availability of Proxy Materials by mail, you will not receive a printed copy of the proxy statement and proxy card unless you request them. Instead, the Notice of Internet Availability of Proxy Materials will instruct you as to how you may access and review the proxy statement, and vote your proxy, on the Internet.

Additional Info:

Registration/Signature Example:

03/30/2026

ACTION REQUIRED

Dear Shareholder,

We have been engaged byJanus Henderson Investors to contact you regarding an important matter relating to the Special Meeting of Shareholders which is to be held on May 18, 2026.

Please vote your shares promptly to ensure they are counted without delay. Voting is easy. You may use one of the options below to ensure that your vote is promptly recorded:

If you have any questions or require further assistance in voting your shares, please contact our proxy solicitor, Alliance Advisors at 1-866-206-7136 from 9:00am to 10:00pm, Eastern time, Monday through Friday.

Thank you in advance for your assistance with this matter.

Sincerely,

Gina Balderas

Operations Manager