Dyadic International Inc 美股招股说明书（2026-03-06版）

Up to $4,237,818Common Stock We have entered into an At the Market Sales Agreement (the “sales agreement”), with Craig-Hallum Capital Group LLC (“Craig-Hallum”), dated March 6, 2026, relating to the sale of shares of our common stock offered by this prospectus supplement. Inaccordance with the terms of the sales agreement, under this prospectus supplement we may offer and sell shares of our common Our common stock is listed on The Nasdaq Capital Market under the trading symbol “DYAI.” On March 5, 2026, the closing price ofour common stock was $0.76 per share. Sales of our common stock, if any, under this prospectus supplement will be made by any method permitted that is deemed an “at themarket offering” as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended, or the Securities Act, including blocktrades and sales made in ordinary brokers’ transactions on The Nasdaq Capital Market or otherwise at market prices prevailing at thetime of sale, at prices related to prevailing market prices or at negotiated prices. Craig-Hallum is not required to sell any specific Craig-Hallum will be entitled to compensation at a commission rate of up to 3.0% of the gross sales price of the shares of our commonstock sold through it pursuant to the sales agreement. See “Plan of Distribution” beginning on page S-10 for additional informationregarding the compensation to be paid to Craig-Hallum. In connection with the sale of the common stock on our behalf, Craig-Hallum As of the date of this prospectus supplement, the aggregate market value of our common stock held by non-affiliates calculatedpursuant to General Instruction I.B.6 of Form S-3 (our “public float”) is $29,961,654, based on 30,888,304 shares of our outstandingcommon stock held by non-affiliates as of March 5, 2026, and a price of $0.97 per share, the closing price of our common stock on Pursuant to General Instruction I.B.6 of Form S-3, in no event will we sell securities in public primary offerings on Form S-3 with avalue exceeding one-third of our public float (as calculated pursuant to General Instruction I.B.6) in any 12-calendar-month period solong as our public float remains below $75.0 million. During the 12 calendar months prior to and including the date of this prospectussupplement, we have offered and sold $5,749,400 of common stock pursuant to General Instruction I.B.6 of Form S-3. As a result, we If our public float increases such that we may sell additional amounts of common stock in excess of the aforementioned aggregateoffering price under the Sales Agreement and the prospectus supplement, we will file another prospectus supplement prior to makingsuch additional sales in excess of the aforementioned aggregate offering price. In the event that our public float increases above $75.0 You should carefully read this prospectus supplement and all information incorporated by reference therein and herein priorto making an investment decision. Investing in our securities involves a high degree of risk. These risks are discussed in this prospectus supplement under “RiskFactors” beginning on page S-5 and in our most recent Annual Report on Form 10-K and Quarterly Reports on Form 10-Qincorporated by reference into this prospectus supplement, and under similar headings in the other documents that are Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of thesesecurities or passed upon the adequacy or accuracy of this prospectus supplement. Any representation to the contrary is acriminal offense. Craig-Hallum The date of this prospectus supplement is March 6, 2026 TABLE OF CONTENTS ABOUT THIS PROSPECTUS SUPPLEMENT This sales agreement prospectus supplement is part of a registration statement that we have filed with the U.S. Securities andExchange Commission, or the SEC, utilizing a “shelf” registration process. By using a shelf registration statement, we may offer We provide information to you about this offering of our common stock in two separate documents that are bound together:(1) this sales agreement prospectus supplement, which describes the specific details regarding this offering; and (2) the accompanyingbase prospectus, which provides general information, some of which may not apply to this offering. Generally, when we refer to this“prospectus supplement,” we are referring to both documents combined. If information in this prospectus supplement is inconsistentwith the accompanying base prospectus, you should rely on this prospectus supplement. To the extent there is a conflict between theinformation contained in this prospectus supplement, on the one hand, and the information contained in any document incorporated by We have not, and Craig-Hallum has not, authorized anyone to provide you with information other than that contained in thisprospectus supplement, the accompanying base prospectus and any free writing prospectus. We are not, and Craig-Hallum is not,makin