Mark McLennan is an intellectual property partner in the New York office of Kirkland & Ellis LLP. He draws on his technical background in pharmacology to represent clients in a range of industries, including pharmaceuticals, biotechnology and medical devices. Mark was recently recognized as a “Key Lawyer” in The Legal 500: Life Sciences 2025.
Mark’s litigation experience extends from pre-suit strategy, all stages of discovery through to bench and jury trials, in addition to inter partes reviews, acting for both Patent Owners and Petitioners. Mark has extensive trial experience, where his roles have included pretrial arguments and examination of fact and expert witnesses. While he focuses his practice on patent litigation, Mark also counsels clients on patenting strategy and due diligence.
Mark brings an international perspective to his practice, with experience in global litigation coordination, a secondment in the London office of Kirkland & Ellis, and having practiced in Australia for several years.
Mark’s pro bono practice includes advocating for persons seeking asylum. He recently second chaired a two-week evidentiary hearing in a Texas capital case, securing commutation of his client’s death sentence to life imprisonment — an achievement honored with the Texas Defender Service’s 2024 Light of Justice Award. Mark is also involved in Kirkland’s inclusion efforts, serving on the leadership committee of the Firm’s Pride Affinity Group.
