DYADIC INTERNATIONAL INC

S-11 forms-1.htm S-1

As filed with the Securities and Exchange Commission on September 11, 2026

Registration No. 333 -

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-1

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

DYADIC INTERNATIONAL, INC.

(Exact name of registrant as specified in its charter)

1044 North U.S. Highway One, Suite 201

Jupiter, Florida 33477

(561) 743-8333

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Mark Emalfarb

Chief Executive Officer

Dyadic International, Inc.

1044 North U.S. Highway One, Suite 201

Jupiter, Florida 33477

(561) 743-8333

(Name, address, including zip code, and telephone number, including area code, of agent for service)

With a copy to:

**Approximate date of commencement of proposed sale to the public:**As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this preliminary prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and we are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

PRELIMINARY PROSPECTUS

SUBJECT TO COMPLETION, DATED SEPTEMBER 11, 2026

3,625,000 Shares

DYADIC INTERNATIONAL, INC.

This prospectus relates to the offer and resale from time to time by the selling stockholders named in this prospectus (the “Selling Stockholders”) of up to 3,625,000 shares of our common stock, par value $0.001 per share, issuable upon the exercise of warrants at an exercise price of $0.84 per share (the “Warrants”).

We will receive proceeds from any exercise of the Warrants, however, there is no guarantee that any Warrants will be exercised. The shares of our common stock may be sold publicly or through private transactions by the Selling Stockholders at prevailing market prices or at negotiated prices at the times of sale. The shares of our common stock may be offered by the Selling Stockholders to or through underwriters, dealers or other agents, directly to investors or through any other manner permitted by law, on a continued or delayed basis. See the section titled “Plan of Distribution” beginning on page 14 of this prospectus.

We are not selling any shares of our common stock in this offering, and we will not receive any proceeds from the sale of shares by the Selling Stockholders. The registration of the securities covered by this prospectus does not necessarily mean that any of these securities will be offered or sold by the Selling Stockholders. The timing and amount of any sale is within the respective Selling Stockholders’ sole discretion, subject to certain restrictions. To the extent that any Selling Stockholder resells any securities, the Selling Stockholder may be required to provide you with this prospectus identifying and containing specific information about the Selling Stockholder and the terms of the securities being offered.

To the extent required by the U.S. Securities Act of 1933, as amended (the “Securities Act”) and the rules and regulations thereunder, the Selling Stockholders and any broker-dealer participating in the distribution of the shares of our common stock may be deemed to be “underwriters” within the meaning of the Securities Act, and any commission paid, or any discounts or concessions allowed to, any such broker-dealer may be deemed to be underwriting commissions or discounts under the Securities Act.

Our common stock is listed on The Nasdaq Capital Market (“Nasdaq”) under the symbol “DYAI.” On September 10, 2026, the last reported sale price of our common stock on Nasdaq was $0.49 per share.

Investing in our common stock involves a high degree of risk. See the section titled “Risk Factors” on page 5 of this prospectus and in the documents incorporated by reference into this prospectus.

Neither the Securities and Exchange Commission (the “SEC”) nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is , 2026.

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