SAB Biotherapeutics Inc美股招股说明书(2026-03-19版)

19,324,677 Shares of Common StockPre-funded Warrants to Purchase up to 2,753,246 Shares of Common Stock 2,753,246Shares of Common Stock Underlying the Pre-funded Warrants We are offering 19,324,677 shares of our common stock, par value $0.0001 per share (“common stock”), and, in lieu of shares ofcommon stock to investors that so choose, pre-funded warrants to purchase up to 2,753,246 shares of our common stock (the “pre-funded warrants”) (and the shares of common stock issuable from time to time upon exercise of the pre-funded warrants), pursuantto this prospectus supplement and the accompanying prospectus. The pre-funded warrants will be exercisable immediately and areexercisable for one share of our common stock. The purchase price of each pre-funded warrant is equal to the purchase price atwhich a share of our common stock is sold in this offering, minus $0.0001, and the exercise price of each pre-funded warrant is$0.0001 per share of our common stock. Our common stock is listed on The Nasdaq Capital Market under the symbol “SABS”. On March 17, 2026, the last reported saleprice for our common stock on The Nasdaq Capital Market was $4.07 per share. There is no established public trading market forthe pre-funded warrants, and we do not expect a market to develop. In addition, we do not intend to apply for listing of the pre-funded warrants on any securities exchange or recognized trading system. We are an “emerging growth company” as defined in Section 2(a) of the Securities Act of 1933, as amended (the “Securities Act”),and a “smaller reporting company” as defined under Rule 405 of the Securities Act, and as such, we have elected to comply withcertain reduced public company reporting requirements. See “Prospectus Supplement Summary— Implications of Being anEmerging Growth Company and a Smaller Reporting Company” on page S-1 of this prospectus. (1)See “Underwriting” for a description of the compensation payable to the underwriters.We have granted the underwriters an option for a period of 30 days to purchase an additional 3,311,688 shares of our common stock from us, at the public offering price, less the underwriting discounts and commissions. If the underwriters exercise the optionin full, the total underwriting discounts and commissions payable by us will be approximately $5.9 million and the total proceeds tous, before expenses, will be approximately $91.9 million. Investing in our securities involves a high degree of risk. Please read the section titled “Risk Factors” beginning on page S-9of this prospectus supplement, page 7 of the accompanying prospectus, and in the documents incorporated by reference intothis prospectus supplement and the accompanying prospectus. Neither the Securities and Exchange Commission nor any state securities commission has approved of anyone's investmentin these securities or determined if this prospectus supplement is truthful or complete. Any representation to the contrary isa criminal offense. Delivery of the shares of common stock and pre-funded warrants is expected to be made on or about March 19, 2026 Joint Bookrunning Managers JefferiesUBS Investment BankCitigroupBarclays Lead Manager Chardan The date of this prospectus supplement is March 17, 2026 TABLE OF CONTENTS ABOUT THIS PROSPECTUS SUPPLEMENT1CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS2PROSPECTUS SUPPLEMENT SUMMARY4THE OFFERING7RISK FACTORS9USE OF PROCEEDS12DIVIDEND POLICY12DILUTION13MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES FOR NON-U.S. HOLDERS OF OURSECURITIES15DESCRIPTION OF PRE-FUNDED WARRANTS20UNDERWRITING22LEGAL MATTERS30EXPERTS30WHERE YOU CAN FIND MORE INFORMATION30INFORMATION INCORPORATED BY REFERENCE30 PageABOUT THIS PROSPECTUS1TRADEMARKS1PROSPECTUS SUMMARY2SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS4RISK FACTORS6USE OF PROCEEDS7DESCRIPTION OF CAPITAL STOCK WE MAY OFFER8DESCRIPTION OF DEBT SECURITIES WE MAY OFFER12DESCRIPTION OF WARRANTS WE MAY OFFER19DESCRIPTION OF RIGHTS WE MAY OFFER21DESCRIPTION OF UNITS WE MAY OFFER22PLAN OF DISTRIBUTION24EXPERTS25LEGAL MATTERS25WHERE YOU CAN FIND MORE INFORMATION25INFORMATION INCORPORATED BY REFERENCE27 ABOUT THIS PROSPECTUS SUPPLEMENT This prospectus supplement and the accompanying base prospectus are part of a registration statement on Form S-3 that we filedwith the Securities and Exchange Commission (the “SEC”) utilizing a “shelf” registration process. The first part is this prospectussupplement, which describes the specific terms of this offering of common stock and pre-funded warrants and also adds to andupdates information contained in the accompanying prospectus and the documents incorporated by reference into this prospectussupplement and the accompanying prospectus.This prospectus supplement is not complete without, and may not be utilized except in connection with, the accompanying base prospectus and any amendments to such prospectus. This prospectus supplement provides you with specific information regardingthe te