Seong Tahk Ahn has been involved in patent prosecution, enforcement, opinion work, portfolio management, licensing and due diligence nationally and internationally for global companies since 1998, and joined Lee & Ko IP in 2015 as a partner to lead the electrical and mechanical patent practice areas. He also has handled chemical and biotechnology patents.

Mr. Ahn has prosecuted patents in a wide variety of technologies, including artificial intelligence (AI), telecommunication, semiconductor, display, computer, semiconductor manufacturing apparatus, business model, internet search, internet network, printing, video and audio signal processing, automotive parts, electronic materials, optics, power generation, automation, biotechnology, chemicals and biotechnology-electronics fusion technology.

Mr. Ahn also has handled invalidation, correction, and confirmation of claim scope trials before the Intellectual Property Tribunal, the Patent Court, and the Supreme Court, and patent infringement suits. He has represented patent infringement cases before the Korean Trade Commission (KTC), and, as an IP adviser to the KTC, has submitted expert opinions in patent infringement cases at the request of the KTC and suggestions on revisions to the KTC Act.

Mr. Ahn has experience providing patent portfolio management service, including review of outside counsels' work and IP budget control, for a global IT company for several years. He also has experience investigating allegedly infringing products, and conducting prior art search to challenge the validity of patents-in-suit.

Based on his study and experience in the US patent practice, Mr. Ahn understands the needs of foreign companies and advises them in complying with the Korean patent practice, and also counsels domestic companies in foreign patent prosecution and litigation matters.

Mr. Ahn is an active member of the AIPPI where he serves as the President of AIPPI-Korea. He was a member of the Organizing Committee for the AIPPI World Congress 2012 Seoul. He has spoken in the AIPPI World Congress and the Korea-Japan-China Trilateral Meetings, and authored Korean chapters of working questions on various IP topics. Mr. Ahn is admitted to the Patent Bar in Korea and the Illinois Bar in the United States, and also passed the US Patent Bar Exam.

Mr. Ahn has been selected as a "Notable practitioner" from Managing IP Awards in 2022.