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STATES\n\nSECURITIES AND EXCHANGE COMMISSION\n\nWASHINGTON, D.C. 20549\n\nFORM 10-Q\n\n(Mark One)\n\n☒\n\nQUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the quarterly period ended March 31, 2026\n\nOR\n\n☐\n\nTRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the transition period from XXXXXXXX XX, XXXX to XXXXXXXX XX, XXXX\n\nCommission File Number: 001-35610\n\nATOSSA THERAPEUTICS, INC.\n\n(Exact Name of Registrant as Specified in its Charter)\n\nDelaware\n\n26-4753208\n\n( State or other jurisdiction of\n\nincorporation or organization)\n\n(I.R.S. Employer\nIdentification No.)\n\n1448 NW Market Street, Suite 500\n\nSeattle, WA\n\n \n\n98107\n\n(Address of principal executive offices)\n\n(Zip Code)\n\nRegistrant’s telephone number, including area code: (206) 588-0256\n\nSecurities registered pursuant to Section 12(b) of the Act:\n\nTitle of each class\n\nTrading\n\nSymbol(s)\n\nName of each exchange on which registered\n\nCommon Stock, $0.18 par value\n\nATOS\n\nThe Nasdaq Capital Market\n\nIndicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐\n\nIndicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐\n\nIndicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, 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.\n\nLarge accelerated filer\n\n☐\n\nAccelerated filer\n\n☐\n\nNon-accelerated filer\n\n☒\n\nSmaller reporting company\n\n☒\n\nEmerging growth company\n\n☐\n\nIf 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 13(a) of the Exchange Act. ☐\n\nIndicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒\n\nAs of May 1, 2026, the registrant had 8,611,361 shares of common stock, $0.18 par value per share, outstanding.\n\n \n\n \n\nATOSSA THERAPEUTICS, INC.\nQUARTERLY REPORT\n\nFORM 10-Q\n\nTABLE OF CONTENTS\n\nPage\n\nPART I.\n\n[FINANCIAL INFORMATION](#financial_information)\n\n3"}