Yeah-Sil Moon is a U.S. and Korean patent attorney. She has extensive experience representing companies in all areas of patent law, including patent litigation, prosecution, opinion, strategic counseling, portfolio creation, and management in the fields of pharmaceuticals, biotechnology, chemicals, automobiles, telecommunications, electronics, and mechanical and medical devices. She has prosecuted and enforced patents in the United States and worldwide for some of the most successful therapeutics developed by pharmaceutical, biotechnology, and medical device companies. She successfully defended patent infringement actions in the U.S. ITC, various district courts, and the U.S. Court of Appeals for the Federal Circuit.

Yeah-Sil has worked for Celgene Corporation, CJ Corporation, Daewoong Pharmaceutical Co., Hyosung Corporation, Hyundai Motor Company, Kia Motor Corporation, the Korea Institute of Science and Technology, the Korea Research Institute of Bioscience and Biotechnology, the Korea Research Institute of Chemistry, LG Household and Healthcare Co., LS Cable Co., Medimmune, Pfizer, Procter & Gamble, SK Chemical Co., and SK Telecom Co.

Yeah-Sil leads the Firm's Korea IP practice and serves on the Firm's Diversity Committee. Before coming to the United States, she worked at Korean IP firms and handled patent prosecution, opinion work, and litigation before the Korean Intellectual Property Office and the Patent Court. Yeah-Sil regularly travels to Korea to speak on U.S. patent procurement, consulting, and litigation matters. She also serves as a member of the Asian Practice Committee of the Intellectual Property Owners (IPO) Association.