Business Combination Prospectus (Form 425)

Filed by Gentherm Incorporated

Pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12

under the Securities Exchange Act of 1934

Subject Company: Gentherm Incorporated

Commission File No.: 000-21810

The following communication is being filed in connection with the proposed business combination between Gentherm Incorporated ("Gentherm") and Platinum SpinCo Inc. ("SpinCo"), a wholly owned subsidiary of Modine Manufacturing Co. ("Modine")

Gentherm All-Employee Note from B. Presley

FROM: Bill Presley

TO: All Gentherm Employees

SUBJECT: Gentherm to Combine with Modine Performance Technologies

Dear Team,

When I joined Gentherm a year ago, we began our journey to create a more resilient company by scaling our core technology across attractive end markets to deliver profitable growth. To accelerate our strategy, today we announced we have entered into an agreement to combine Modine Performance Technologies with Gentherm, which we expect to benefit customers, employees, and shareholders. This combination will establish Gentherm as a scaled leader in thermal management solutions with expanded technologies and capabilities in precision flow management, positioning us for long-term success.

Modine Performance Technologies brings more than 100 years of innovation in highly engineered, mission-critical thermal management solutions across the commercial vehicle, heavy-duty equipment, and fast-growing power generation end markets. Similar to Gentherm, Modine Performance Technologies offers a strong global footprint in 10 countries and approximately 5,000+ employees.

The addition of Modine Performance Technologies accelerates the execution of our strategy, enabling us to serve attractive end markets. We believe that we will benefit from strong commercial opportunities across Modine Performance Technologies' customer bases, where it brings leading brand recognition and deep relationships with blue-chip customers.

Importantly, we have a shared focus on operational excellence and delivering solutions that improve everyday life. The combined company will benefit from Modine Performance Technologies' well-established operating system, alongside our operational excellence culture. Together, we will be an essential technology provider in a broader set of end markets, with more balanced end-market exposure and ample opportunities for future growth.

Next steps

You can learn more about Modine Performance Technologies and this announcement in a video you can watch HERE. The press release we issued regarding this announcement can be found HERE. You will also receive an invitation to join a Town Hall shortly at 7:00 a.m., Eastern Time, where we will discuss the announcement in more detail.

We are committed to communicating with you openly to provide updates when we can. Today's announcement is only the first step in this process.

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Modine Performance Technologies is currently part of Modine. Modine will separate Modine Performance Technologies into its own company, and that company will then combine with Gentherm. We expect the transaction to close in the fourth quarter of calendar year 2026, and until then, Gentherm and Modine Performance Technologies will remain separate and continue to operate independently.

Once the transaction is complete, we will continue to operate under the Gentherm name, and I will continue to lead the company as CEO. Our intent is to run Modine Performance Technologies as a division of Gentherm, where Jeremy Patten, the current President of that business will continue in his role. Our goal will be to ensure each business is able to continue excelling at what they do best, while also allowing us to capture the exciting commercial opportunities this unlocks for us.

This is an early milestone in bringing our long-term strategy to life, and it is possible because of the dedication, innovation, and teamwork you bring to Gentherm every day. As we move forward, our strengths will open new doors and together, we'll shape the future of precision flow management. Let's make the most of this exciting new chapter.

Sincerely,

Bill

NO OFFER OR SOLICITATION

This communication is not intended to and does not constitute an offer to sell or the solicitation of an offer to buy or exchange any securities or a solicitation of any vote or approval in any jurisdiction, nor shall there be any sale, issuance or transfer of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. It does not constitute a prospectus or prospectus equivalent document. No offering or sale of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended (the "Securities Act"), and otherwise in accordance with applicable law.

Additional Information and Where to Find It

In connection with the proposed transaction between Modine, SpinCo and Gentherm (the "Proposed Transaction"), the parties intend to file relevant materials with the U.S. Securities and Exchange Commission (the "SEC"), including, among other filings, a registration statement on Form S-4 to be filed by Gentherm (the "Form S-4") that will include a preliminary proxy statement/prospectus of Gentherm and a definitive proxy statement/prospectus of Gentherm, the latter of which will be mailed to shareholders of Gentherm, and a registration statement on Form 10 to be filed by SpinCo that will incorporate by reference certain portions of the Form S-4 and will serve as an information statement/prospectus in connection with the spin-off of SpinCo from Modine. INVESTORS AND SECURITY HOLDERS OF GENTHERM AND MODINE ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS, THE INFORMATION STATEMENT/PROSPECTUS AND ANY OTHER DOCUMENTS THAT WILL BE FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THESE DOCUMENTS, CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT GENTHERM, MODINE, SPINCO, THE PROPOSED TRANSACTION AND RELATED MATTERS. Investors and security holders will be able to obtain free copies of the Form S-4 and the proxy statement/prospectus (when available) and other documents filed with the SEC by Gentherm, SpinCo or Modine through the website maintained by the SEC at www.sec.gov. Copies of the documents filed with the SEC by Gentherm will be available free of charge on Gentherm's website at ir.Gentherm.com under the tab "Financial Info" and under the heading "SEC Filings." Copies of the documents filed with the SEC by Modine and SpinCo will be available free of charge on Modine's website at investors.Modine.com under the tab "Financials" and under the heading "SEC Filings."

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Participants in the Solicitation

Gentherm, Modine and their respective directors and executive officers and other members of management and employees may be considered participants in the solicitation of proxies from Gentherm stockholders in connection with the Proposed Transaction. Information about the directors and executive officers of Gentherm is set forth in its Annual Report on Form 10-K for the year ended December 31, 2024, which was filed with the SEC on February 19, 2025, and its proxy statement for its 2025 annual meeting of shareholders, which was filed with the SEC on March 27, 2025. To the extent holdings of Gentherm's securities by its directors or executive officers have changed since the amounts set forth in such filings, such changes have been or will be reflected on Initial Statements of Beneficial Ownership on Form 3 or Statements of Beneficial Ownership on Form 4 filed with the SEC. Information about the directors and executive officers of Gentherm and other information regarding the potential participants in the proxy solicitations and a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the proxy statement/prospectus and other relevant materials to be filed with the SEC regarding the Proposed Transaction. Information about the directors and executive officers of Modine is set forth in its Annual Report on Form 10-K for the year ended March 31, 2025, which was filed with the SEC on May 21, 2025, and its proxy statement for its 2025 annual meeting of shareholders, which was filed with the SEC on July 9, 2025. To the extent holdings of Modine's securities by its directors or executive officers have changed since the amounts set forth in such filings, such changes have been or will be reflected on Initial Statements of Beneficial Ownership on Form 3 or Statements of Beneficial Ownership on Form 4 filed with the SEC. You may obtain these documents (when they become available) free of charge through the website maintained by the SEC at www.sec.gov and from Gentherm's website and Modine's website as described above.

Cautionary Statement Regarding Forward-Looking Statements

This communication includes "forward-looking statements" as that term is defined in Section 27A of the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, including statements regarding the Proposed Transaction among Gentherm, Modine and SpinCo. These forward-looking statements may be identified by the words "believe," "feel," "project," "expect," "anticipate," "appear," "estimate," "forecast," "outlook," "target," "endeavor," "seek," "predict," "intend," "suggest," "strategy," "plan," "may," "could," "should," "will," "would," "will be," "will continue," "will likely result," or the negative thereof or variations thereon or similar terminology generally intended to identify forward-looking statements. All statements, other than historical facts, including, but not limited to, statements regarding the expected timing and structure of the Proposed Transaction, the ability of the parties to complete the Proposed Transaction, the expected benefits of the Proposed Transaction, including future financial and operating results, anticipated strategic benefits of the Proposed Transaction, the amount and timing of synergies from the Proposed Transaction, the tax consequences of the Proposed Transaction, the terms and scope of the expected financing in connection with the Proposed Transaction, the aggregate amount of indebtedness of the combined company following the closing of the Proposed Transaction, the combined company's plans, objectives, expectations and intentions, legal, economic and regulatory conditions, and any assumptions underlying any of the foregoing, are forward-looking statements.

These forward-looking statements are based on Gentherm's and Modine's current expectations and are subject to risks and uncertainties surrounding future expectations generally. Actual results could differ materially from those currently anticipated due to a number of risks and uncertainties, many of which are beyond Gentherm's and Modine's control. None of Gentherm, Modine, SpinCo or any of their respective directors, executive officers, advisors or representatives make any representation or provide any assurance or guarantee that the occurrence of the events expressed or implied in any forward-looking statements will actually occur, or if any of them do occur, what impact they will have on the business, results of operations or financial condition of Gentherm, Modine or the combined business. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those indicated or anticipated by such forward-looking statements, including developments that could have a material adverse effect on Gentherm's and Modine's businesses and the ability to successfully complete the Proposed Transaction and realize its benefits. The inclusion of such statements should not be regarded as a representation that such plans, estimates or expectations will be achieved. Important factors that could cause actual results to differ materially from such plans, estimates or expectations include, among others, (1) that one or more closing conditions to the Proposed Transaction, including certain regulatory approvals, may not be satisfied or waived, on a timely basis or otherwise, including that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the Proposed

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Transaction, may require conditions, limitations or restrictions in connection with such approvals or that the required approval by the shareholders of Gentherm may not be obtained; (2) the risk that the Proposed Transaction may not be completed on the terms or in the time frame expected by Gentherm, Modine and SpinCo, or at all; (3) unexpected costs, charges or expenses resulting from the Proposed Transaction; (4) uncertainty of the expected financial performance of the combined company following completion of the Proposed Transaction; (5) failure to realize the anticipated benefits of the Proposed Transaction, including as a result of delay in completing the Proposed Transaction or integrating the businesses of Gentherm and SpinCo, on the expected timeframe or at all; (6) the ability of the combined company to implement its business strategy; (7) difficulties and delays in the combined company achieving revenue and cost synergies; (8) inability of the combined company to retain and hire key personnel; (9) the occurrence of any event that could give rise to termination of the Proposed Transaction; (10) the risk that shareholder litigation in connection with the Proposed Transaction or other litigation, settlements or investigations may affect the timing or occurrence of the Proposed Transaction or result in significant costs of defense, indemnification and liability; (11) evolving legal, regulatory and tax regimes; (12) changes in general economic and/or industry specific conditions or any volatility resulting from the imposition of and changing policies, including those policies with respect to tariffs; (13) actions by third parties, including government agencies; (14) the risk that the anticipated tax treatment of the Proposed Transaction is not obtained; (15) the risk of greater than expected difficulty in separating the business of SpinCo from the other businesses of Modine; (16) risks related to the disruption of management time from ongoing business operations due to the pendency of the Proposed Transaction, or other effects of the pendency of the Proposed Transaction on the relationship of any of the parties to the Proposed Transaction with their employees, customers, suppliers, or other counterparties; and (17) other risk factors detailed from time to time in Gentherm's and Modine's reports filed with the SEC, including Gentherm's and Modine's annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and other documents filed with the SEC, including documents that will be filed with the SEC in connection with the Proposed Transaction. The foregoing list of important factors is not exclusive.

Any forward-looking statements speak only as of the date of this communication. None of Gentherm, Modine or SpinCo undertakes, and each party expressly disclaims, any obligation to update any forward-looking statements, whether as a result of new information or development, future events or otherwise, except as required by law. Readers are cautioned not to place undue reliance on any of these forward-looking statements.

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