Emalfarb holds 17.5% of Dyadic (NASDAQ: DYAI) via shares, options, note

Rhea-AI Filing Summary

Dyadic International Inc. filed an amended Schedule 13G showing that Mark A. Emalfarb beneficially owns 6,675,439 shares of Dyadic common stock, representing 17.5% of the class based on 36,187,798 shares outstanding as of December 31, 2025.

The position includes 993,000 shares underlying presently exercisable options, 4,730,058 shares held through the MAE Trust, and 952,381 shares underlying an 8.0% Senior Secured Convertible Promissory Note due December 31, 2027, convertible at $1.05 per share. Emalfarb has sole voting and dispositive power over all reported shares through his role as sole trustee and beneficiary of the MAE Trust.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 5)

DYADIC INTERNATIONAL INC.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

26745T101

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 26745T101

1

Names of Reporting Persons

Mark A. Emalfarb

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 6,675,439.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 6,675,439.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

6,675,439.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

17.5 %

12

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person: 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.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: DYADIC INTERNATIONAL INC.
(b)	Address of issuer's principal executive offices: 1044 North U.S. Highway One, Suite 201, Jupiter, Florida, 33477
Item 2.
(a)	Name of person filing: Mark A. Emalfarb
(b)	Address or principal business office or, if none, residence: 1044 North U.S. Highway One, Suite 201, Jupiter, Florida, 33447
(c)	Citizenship: United States of America
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 26745T101
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 6,675,439
(b)	Percent of class: 17.5%
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 6,675,439
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 6,675,439
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.	Certifications:
	Not Applicable

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Mark A. Emalfarb

Signature:	/s/ Mark Emalfarb
Name/Title:	Self
Date:	02/17/2026

FAQ

What ownership stake in DYAI does Mark A. Emalfarb report in this Schedule 13G/A?

Mark A. Emalfarb reports beneficial ownership of 6,675,439 Dyadic common shares, representing 17.5% of the class. This percentage is based on 36,187,798 shares outstanding as of December 31, 2025, as reported to him by the company.

How is Mark A. Emalfarb’s DYAI ownership structured, including the MAE Trust and options?

His 6,675,439-share beneficial stake includes 993,000 shares underlying presently exercisable options and 4,730,058 shares held through the MAE Trust. It also includes 952,381 shares underlying a convertible note held via the MAE Trust, all under his sole voting and dispositive power.

What are the key terms of the Dyadic 8.0% Senior Secured Convertible Promissory Note?

The filing describes an 8.0% Senior Secured Convertible Promissory Note maturing on December 31, 2027. Interest is payable quarterly in cash at 8% per year, and the note is convertible into Dyadic common stock at a price of $1.05 per share.

What role does the MAE Trust play in Mark A. Emalfarb’s DYAI share ownership?

The MAE Trust holds 4,730,058 Dyadic shares and the convertible note for 952,381 underlying shares. Emalfarb is the sole beneficiary and sole trustee, giving him sole voting and dispositive power over all Dyadic securities owned through the MAE Trust.

Does Mark A. Emalfarb have sole or shared voting power over his DYAI shares?

He reports sole voting power and sole dispositive power over all 6,675,439 beneficially owned shares. The Schedule 13G/A shows zero shared voting or shared dispositive power, reflecting his control, including over securities held through the MAE Trust.