SCHEDULE 13G/A 0001493152-25-023646 0001328287 XXXXXXXX LIVE 5 Common Stock 12/31/2025 0001213809 DYADIC INTERNATIONAL INC. 26745T101 1044 North U.S. Highway One, Suite 201 Jupiter FL 33477 Rule 13d-1(d) Mark A. Emalfarb X1 6675439.00 0.00 6675439.00 0.00 6675439.00 N 17.5 IN Includes (i) 993,000 shares of common stock underlying options present exercisable, (ii) 4,730,058 shares held through the MAE Trust U/A/D October 1, 1987 (the "MAE Trust"), and (iii) 952,381 shares underlying an 8.0% Senior Secured Convertible Promissory Note due December 31, 2027, convertible at any time at the holder's option (the "Convertible Note"), held through the MAE Trust. Mr. Emalfarb is the sole beneficiary and sole trustee of, and has sole voting and dispositive power over all shares held or otherwise owned through, the MAE Trust. The Convertible Notes are senior, secured obligations of the Issuer and its affiliates, and interest is payable quarterly in cash on the principal amount equal to 8% per annum. The Convertible Notes (following an amendment made on December 23, 2025) will mature on December 31, 2027, unless earlier converted, repurchased, or redeemed in accordance with their terms, and have a conversion price of $1.05 per share of common stock. The ownership percentage is based on 36,187,798 shares of common stock of the Issuer outstanding as of December 31, 2025, as reported by the Issuer to Mr. Emalfarb. DYADIC INTERNATIONAL INC. 1044 North U.S. Highway One, Suite 201, Jupiter, Florida, 33477 Mark A. Emalfarb 1044 North U.S. Highway One, Suite 201, Jupiter, Florida, 33447 United States of America Y 6,675,439 17.5% 6,675,439 0 6,675,439 0 Y Y Y Y Y Y Mark A. Emalfarb /s/ Mark Emalfarb 02/17/2026