As filed with the Securities and Exchange Commission on August 10, 2026

Registration No. 333-297224

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 2

to

FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

GENTHERM INCORPORATED

(Exact name of registrant as specified in its charter)

28875 Cabot Drive

Novi, Michigan 48377

(248) 504-0500

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

Wayne Kauffman, Esq.

Senior Vice President, General Counsel and Secretary

Gentherm Incorporated

28875 Cabot Drive

Novi, Michigan 48377

(248) 504-0500

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

With copies to:

Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable after this Registration Statement is declared effective and the date on which all other conditions to the Distribution and Merger 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 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 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 or until the registration statement shall become effective on such date as the Commission acting pursuant to said Section 8(a), may determine.

EXPLANATORY NOTE

Gentherm Incorporated is filing this Amendment No. 2 to the Registration Statement on Form S-4 (File No. 333-297224), originally filed on July 2, 2026 and amended on August 5, 2026 (as amended, the “Registration Statement”), to file new Exhibits 8.2 and 107. Accordingly, this Amendment No. 2 consists only of the facing page, this explanatory note and Item 21 of Part II of the Registration Statement. The remainder of the Registration Statement is unchanged and has thus been omitted.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 21. Exhibits and Financial Statements Schedules

The following is a list of exhibits filed as part of this proxy statement/prospectus.

II-1

SIGNATURES

Pursuant to the requirements of the Securities Act, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the Town of Novi, Michigan, on this 10th day of August, 2026.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities indicated as of the 10th day of August, 2026.

II-2

EXHIBIT 8.2

				Gibson, Dunn & Crutcher LLP   200 Park Avenue New York, NY 10166 Tel +1 650.849.5300 www.gibsondunn.com

August 5, 2026

Modine Manufacturing Company

1500 DeKoven Avenue

Racine, Wisconsin 53403

Ladies and Gentlemen:

We have acted as U.S. tax counsel to Modine Manufacturing Company, a Wisconsin corporation (“Modine”), in connection with (i) the proposed distribution (the “Distribution”) of shares of common stock of Platinum SpinCo Inc., a Delaware corporation and a wholly owned indirect subsidiary of Modine (“SpinCo”), by Modine to holders of shares of its common stock (“Modine Common Stock”), and certain other related transactions, followed by (ii) the merger (the “Merger”) of Platinum Gold Merger Sub Inc., a Delaware corporation and a wholly owned subsidiary of Gentherm Incorporated, a Michigan corporation (“Gentherm”), with and into SpinCo, with SpinCo continuing as the surviving corporation and becoming a wholly owned subsidiary of Gentherm.¹ At your request, and in connection with the filing by Gentherm of the registration statement on Form S-4 (Registration No. 333-297224) (including the proxy statement/prospectus contained therein, the “Registration Statement”), this letter sets forth our opinion (the “Opinion”) concerning certain U.S. federal income tax consequences of the Distribution and the Merger (collectively, the “Transactions”).

In connection with the Opinion, we have examined and relied on the Merger Agreement, the Separation and Distribution Agreement dated as of January 29, 2026, by and among Modine, Gentherm, and SpinCo (the “Separation Agreement”), the form of Tax Matters Agreement by and among Modine, SpinCo, and Gentherm attached to the Merger Agreement (the “Tax Matters Agreement”), the Registration Statement (collectively, the “Transaction Documents”), the request for a private letter ruling submitted by Modine to the Internal Revenue Service (the “IRS”) on June 3, 2026 (including all exhibits and other attachments to that request), together with all supplemental filings related to such request submitted by Modine to the IRS through the date of the Opinion (collectively, the “IRS Ruling Request”), and such other documents as we

Modine Manufacturing Company

August 5, 2026

Page 2

have deemed necessary or appropriate to render the Opinion. We have also relied on the accuracy and completeness of certain statements, representations, warranties, covenants, and information provided by representatives of Modine and Gentherm, including the accuracy and completeness of all statements and representations set forth in the officer’s certificates dated as of the date hereof received by us from each of Modine, on behalf of itself and SpinCo, and Gentherm (collectively, the “Officer’s Certificates”). In our examination, we have assumed the genuineness of all signatures, the legal capacity of natural persons, the due authorization, execution and delivery of the Transaction Documents, the enforceability of the Transaction Documents, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as duplicates or certified or conformed copies, and the authenticity of the originals of such latter documents. We have not, however, undertaken any independent investigation of any factual matter set forth in any of the foregoing.

For purposes of the Opinion, we have assumed that (i) the Transactions will be consummated in the manner described in the Transaction Documents, the IRS Ruling Request, and the Officer’s Certificates, and none of the material terms and conditions of the Transaction Documents have been or will be waived or modified, (ii) the statements, representations, warranties, covenants, and information set forth in the Transaction Documents, the IRS Ruling Request, and the Officer’s Certificates are true, complete, and correct and will remain true, complete, and correct at all times up to and including the Closing and thereafter, (iii) any such statements, representations, warranties, covenants, or information qualified by knowledge, intention, belief, or any other similar qualification are true, complete, and correct, and will remain true, complete, and correct at all times up to and including the Closing and thereafter, in each case as if made without that qualification, (iv) there are no documents or understandings between any of the Parties that would alter, or are inconsistent with, the terms or representations set forth in the Transaction Documents, the IRS Ruling Request, and the Officer’s Certificates, and (v) the IRS will grant the rulings requested in the IRS Ruling Request in substantially the form so requested. We have also assumed that (1) the Parties have complied with, and will continue to comply with, the obligations, covenants, and agreements contained in the Transaction Documents, (2) representation letters made as of the time of the Transactions that are substantially similar to the Officer’s Certificates will be executed and delivered to us by appropriate officers of each of Modine and Gentherm, and (3) we will deliver the Distribution Tax Opinion and the Company Merger Tax Opinion as of the Closing Date as contemplated by the Merger Agreement. In addition, the Opinion is based solely on the documents that we have examined, the additional information that we have obtained, and the statements referred to above. No assurance can be given as to the effect on the Opinion if any of the foregoing assumptions is or becomes inaccurate.

Modine Manufacturing Company

August 5, 2026

Page 3

The Opinion does not address the application of section 355(e) to the Distribution or the U.S. federal income tax consequences of the Distribution to Modine. As described in the Registration Statement, Modine intends to rely on the IRS Ruling with respect to, among other things, the application of the overlapping shareholder exception in section 355(e)(3)(A)(iv) to establish that one or more persons will not acquire directly or indirectly equity representing a 50-percent or greater interest in Modine or SpinCo for purposes of section 355(e). Modine’s obligation to complete the Transactions is conditioned on the receipt of the IRS Ruling and its continuing effectiveness and validity.

Based on and subject to the foregoing, and subject to the assumptions and qualifications set forth herein and in the Registration Statement, we are of the opinion that, under current U.S. federal income tax law:

Modine Manufacturing Company

August 5, 2026

Page 4

We express no opinion on any issue relating to the tax consequences of the Transactions contemplated by the Registration Statement other than the Opinion set forth above. The Opinion is based on current provisions of the Code, the Treasury Regulations, published pronouncements of the IRS, and case law, any of which may be changed at any time with retroactive effect. Any change in applicable laws or the facts and circumstances surrounding the Transactions, or any inaccuracy in the statements, facts, assumptions, or representations upon which we have relied, may affect the continuing validity of the Opinion as set forth in this letter. We assume no responsibility to inform you of any such change or inaccuracy that may occur or come to our attention.

We are furnishing the Opinion to you in connection with the filing of the Registration Statement, and the Opinion letter may not be relied on for any other purpose without our prior written consent. We hereby consent to the filing of the Opinion with the Securities and Exchange Commission as an exhibit to the Registration Statement and to the references to our firm name in the Registration Statement. In giving such consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended, or the rules and regulations of the Securities and Exchange Commission thereunder.

Very truly yours,

/s/ Gibson, Dunn & Crutcher LLP