[Form 4] DYADIC INTERNATIONAL INC Insider Trading Activity

Rhea-AI Filing Summary

Mark A. Emalfarb, who is listed as CEO, a director and a >10% owner of Dyadic International, purchased a $1,000,000 principal Senior Secured Convertible Promissory Note of Dyadic International on 09/15/2025. The note accrues interest at 8% per annum payable quarterly and matures on March 8, 2027 unless earlier converted, repurchased, or redeemed.

The note is convertible at $1.40 per share, representing 714,286 underlying common shares if converted in full. The reported ownership is held indirectly through the Mark A Emalfarb Trust U/A/ DTD 10/1/1987. The Form 4 was signed by an attorney-in-fact on behalf of the reporting person on 09/17/2025.

Insights

Financial Analyst

TL;DR: Insider purchased a $1.0M secured convertible note with fixed 8% cash interest and a $1.40 conversion price, creating potential share dilution.

The instrument combines debt-like cash interest with equity conversion optionality. The 8% coupon provides immediate cash yield to the holder while the $1.40 conversion price makes conversion economics sensitive to the company’s share price trajectory. The note is senior and secured, indicating creditor priority until conversion, and it matures in March 2027, which sets a time horizon for either repayment or conversion decisions. For investors, the direct metrics to monitor are the company’s share price relative to $1.40 and any subsequent conversions or repurchases that would affect share count and capital structure.

Corporate Governance Expert

TL;DR: A significant insider transaction: a material convertible financing by a >10% owner and executive, reported as indirect ownership via a trust.

Transaction structure—senior secured convertible note held indirectly by the Emalfarb Trust—raises governance considerations around related-party financing terms and transparency. The Form 4 discloses key terms including principal amount, coupon, conversion price, and maturity, but does not disclose collateral specifics or any related-party approval process. Investors should expect further disclosures if conversion occurs or if any related-party agreements are implemented affecting corporate governance or capitalization.

SEC Form 4

FORM 4

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
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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hours per response:			0.5

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

1. Name and Address of Reporting Person^*

EMALFARB MARK A

(Last) (First) (Middle)

C/O DYADIC INTERNATIONAL, INC.

1044 NORTH U.S. HIGHWAY ONE, SUITE 201

(Street)

JUPITER FL 33477-5094

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
DYADIC INTERNATIONAL INC [ DYAI ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
X	Officer (give title below)		Other (specify below)
	CEO

3. Date of Earliest Transaction (Month/Day/Year)
09/15/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	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

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 (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	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 (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (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: 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
Senior Secured Convertible Promissory Note due March 8, 2027	$1.4	09/15/2025		P		$1,000,000(1)		(1)	03/08/2027	Common Stock	714,286	$1,000,000(1)	$1,000,000(1)	I	Through Mark A Emalfarb Trust U/A/ DTD 10/1/1987

Explanation of Responses:

1. Represents a purchase of $1,000,000 principal amount of Senior Secured Convertible Promissory Note due March 8, 2027 (the "Convertible Notes.") 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 will mature on March 8, 2027, unless earlier converted, repurchased, or redeemed in accordance with their terms. The Convertible Notes have a conversion price of $1.40 per share of common stock.

	/s/ Ping Rawson, attorney-in-fact	09/17/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did DYAI insider Mark A. Emalfarb acquire on 09/15/2025?

He purchased a $1,000,000 principal Senior Secured Convertible Promissory Note due March 8, 2027 with 8% annual cash interest.

What is the conversion price and how many shares could be issued for DYAI?

The note converts at $1.40 per share, which corresponds to 714,286 underlying common shares if converted in full.

How is the acquired security held for DYAI reporting purposes?

The holdings are reported as indirect through the Mark A Emalfarb Trust U/A/ DTD 10/1/1987.

When does the DYAI convertible note mature and when is interest paid?

The note matures on March 8, 2027 and interest is payable quarterly in cash at an 8% annual rate.

Who signed the Form 4 for this DYAI transaction?

The Form 4 was signed by Ping Rawson, attorney-in-fact on behalf of the reporting person on 09/17/2025.