As filed with the Securities and Exchange Commission on June 14, 2024. THE SECURITIES ACT OF 1933 APTEVO THERAPEUTICS INC. (Exact Name of Registrant as Specified in Its Charter) Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER (State or Other Jurisdiction of Incorporation or Organization) (Primary Standard Industrial (Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent For Service) Copies to ...