Sec Form 4 Filing - TRINA SOLAR (SCHWEIZ) AG @ T1 Energy Inc. - 2025-12-03

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person TRINA SOLAR (SCHWEIZ) AG 2. Issuer Name and Ticker or Trading Symbol T1 Energy Inc. [ TE] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) BIRKENWEG 4 3. Date of Earliest Transaction (MM/DD/YY) 12/03/2025 (Street) WALLISELLEN, V88304 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Shares 12/10/2025 C 17,918,460 A 45,877,960 D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares 7% Unsecured Convertible Note Due in 2030 ( 1 ) 12/03/2025 J( 1 ) 17,918,460 ( 1 ) ( 1 ) Common Stock 30,400,000 ( 1 ) 30,400,000 D 7% Unsecured Convertible Note Due in 2030 ( 1 ) 12/10/2025 C 17,918,460 ( 1 ) ( 1 ) Common Stock 17,918,460 ( 1 ) 0 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other TRINA SOLAR (SCHWEIZ) AG BIRKENWEG 4 WALLISELLEN, V88304 X Signatures Trina Solar (Schweiz) AG By: Vincenzo Costanzelli, Chairman of the Board of Directors 12/30/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )As reported in the Form 8-K filed by the Issuer on 12/27/24, on 12/23/24, in connection with an acquisition transaction, the Issuer issued to the Reporting Person a 7% convertible note (the ?Note?). Subject to approval by the Committee on Foreign Investment in the United States ("CFIUS"), the Note was convertible by the Reporting Person into (i) 12,521,653 shares of common stock of the Issuer (the "First Conversion") and (ii) an additional 17,918,460 shares of common stock of the Issuer (the "Second Conversion"). The Second Conversion was subject to approval by the Issuer's stockholders. On 5/27/25, the Issuer received a CFIUS letter determining that the transaction was not a covered transaction under Section 721 of the Defense Production Act of 1950, as amended, and therefore was not subject to review by CFIUS. The First Conversion occurred on 9/5/25. The Issuer's stockholders approved the Second Conversion on 12/3/25, and the Second Conversion occurred on 12/10/25.

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