Mark A. Emalfarb - 23 Dec 2025 Form 4 Insider Report for DYADIC INTERNATIONAL INC (DYAI)

Reporting relationship: CEO, Director, 10%+ Owner
Issuer ticker: DYAI
Reported as of: 23 Dec 2025
Net transaction value: $0
SEC form: 4
Accepted by SEC: 29 Dec 2025, 17:00:32 UTC
Prior SEC filing: 17 Sep 2025
Next SEC filing: 06 Jan 2026
Source filing: View source filing
Reporting owner signature: /s/ Ping Rawson, attorney-in-fact

Key filing fact

Mark A. Emalfarb filed Form 4 for DYADIC INTERNATIONAL INC (DYAI) on 29 Dec 2025.

Key facts

This page summarizes Mark A. Emalfarb's Form 4 filing for DYADIC INTERNATIONAL INC (DYAI).
2 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 29 Dec 2025, 17:00.

Change

Previous filing in this sequence was filed on 17 Sep 2025.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001328287 Primary reporting owner

EMALFARB MARK A

Relationship: CEO, Director, 10%+ Owner
Address: C/O DYADIC INTERNATIONAL, INC., 1044 NORTH U.S. HIGHWAY ONE, SUITE 201, JUPITER
Signature: /s/ Ping Rawson, attorney-in-fact
Signature date: 29 Dec 2025

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

DYAI transaction Derivative

Senior Secured Convertible Promissory Note due March 8, 2027

Disposed to Issuer

Transaction value: $1,000,000
Shares
Change %
Price
Shares after: 0
Date: 23 Dec 2025
Ownership: Through Mark A Emalfarb Trust U/A/ DTD 10/1/1987
Underlying class: Common Stock
Underlying amount: 714,286
Exercise price: $1.40
Footnotes: F1

DYAI transaction Derivative

Senior Secured Convertible Promissory Note due Dec 31, 2027

Award

Transaction value: $1,000,000
Shares
Change %
Price
Shares after: $1,000,000
Date: 23 Dec 2025
Ownership: Through Mark A Emalfarb Trust U/A/ DTD 10/1/1987
Underlying class: Common Stock
Underlying amount: 952,381
Exercise price: $1.05
Footnotes: F1

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 1 footnote

Footnote F1

On December 23, 2025, Dyadic International, Inc. (the "Company") entered into an amendment (the "Amendment") to the Form of Senior Secured Convertible Promissory Note due March 8, 2027 (the "Convertible Notes"). Following the Amendment, the Convertible Notes will mature December 31, 2027 and their conversion price is $1.05. The Amendment was approved by the Company's board of directors, and did not involve the exchange of consideration between the Company and the holders.