18 Intellectual Property We strive to protect and enhance the proprietary technology, inventions, and improvements that are commercially important to our business, including seeking, maintaining, and defending patent rights. We seek to protect our proprietary position by, among other methods, filing patent applications in the United States and in jurisdictions outside of the United States related to our proprietary technology, inventions, improvements, and product candidates that are important to the development and implementation of our business. We also rely on trade secrets and know-how relating to our proprietary technology and product candidates and continuing innovation to develop, strengthen, and maintain our proprietary position in the field. Although we are not party to any material in-license agreements as of the date of this Annual Report on Form 10-K, we may in the future pursue in-licensing opportunities to strengthen our proprietary position in the field. We additionally rely on data exclusivity, market exclusivity, and patent term extensions when availabl a e, and may seek and rely on regulatory r protection affo f rded through orpha r n drug r designations. Our commercial success may depend in part on our ability to obtain and maintain patent and other proprietary protection for our technology, inventions, and improvements; to preserve the confid f entiality of our trade secrets; to defend and enforce our proprietary rights, including our patents; and to operate without infringing the valid and enforceable patents and other proprietary rights of third parties. We have prosecuted numerous patents and patent applications and possess know-how and trade secrets relating to the development and commercialization of our ABC Platform and product candidates, including related manufact f ur t ing processes and technology. As of December 31, 2023, we were the assignee of record for approximately 11 U.S. issued patents, and the applicant for approximately 20 U.S. pending patent applications and 4 pending PCT applications directed to certain of our proprietary technology, inventions, and improvements and our most advanced product candidates, as well as 48 patents issued in jurisdictions outside of the United States and 59 patent applications pending in jurisdictions outside of the United States that, in many cases, are counterpa r rts to the foregoing U.S. patents and patent applications. For example, these patents and patent applications include claims directed to: • therapeutic proteins and biologically active agents conjugated to a biopolymer, which comprise our ABC Platform; • specific therapeutics, including tarcocimab; and • components of our therapeutics. The following patents and patent applications (including anticipated 20-year expiration dates, which could be altered by, for example, a disclaimer, patent term adju d stment or patent term extension) relate to tarcocimab, a KSI-501, and/or ABC Platform: Patent and Patent Application Numbers Anticipated U.S. Expiration Date Description of Representative U.S. Claims US 8,846,021, US Appl. No. 17/553,605, EP Patent No. 1988910, JP Patent No. 5528710, JP Patent No. 5745009, and foreign applications in certain jurisdictions claiming priority to PCT/US2007/005372 2/28/2027 Representative claims include conjugates US Appl. No. 17/409,578, AU Patent No. 2011239434, AU Patent No. 2017201930, BR Patent No. 11 2012 0261185, CA Patent No. 2795667, EP Patent No. 2558538, EP Patent No. 3549963, HK Patent No. 40015590, JP Patent No. 6568748, JP Patent No. 6754749, KR Patent No. 10- 2416359, MX Patent No. 365521, and foreign applications in certain jurisdictions claiming priority to PCT/US2011/032768 4/15/2031 Representative claims include conjugates