Overview
(September 17, 2025, New York) – Steptoe LLP is expanding its sophisticated patent counseling practice across the biotechnology and pharmaceutical sectors with the addition of Yi Han Dulkeith, Ph.D., who joins from Jones Day as a partner in the firm's New York office. Yi brings a rare combination of scientific depth, global perspective, and strategic legal insight to Steptoe's Life Sciences practice.
Yi's practice spans strategic global patent portfolio development, patent prosecution, freedom-to-operate and invalidity analyses, due diligence, and post-grant proceedings. She has advised multinational biopharmaceutical companies, healthcare organizations, startups, and investors on cutting-edge technologies including antibody therapeutics, cell therapies, gene therapies, and diagnostics.
"Yi's deep technical insight and strategic understanding of life sciences innovation are a strong complement to Steptoe's global IP practice," said Steptoe chair Gwen Renigar. "Her skills align with our clients' needs to navigate complex patent landscapes at the intersection of evolving policy, regulatory frameworks, and commercial imperatives."
At Steptoe, Yi will play a key role in expanding the firm's market-leading biotech patent work. Her background in molecular biology, bilingual fluency in Mandarin and English, and experience advising both US and Chinese companies position her to enhance Steptoe's cross-border capabilities in competitive therapeutic areas such as antibody therapeutics, cell and gene therapies, and molecular diagnostics.
"Steptoe's collaborative approach and global reach align perfectly with my passion for helping biotech pioneers protect and commercialize transformative technologies," said Yi. "I look forward to working with the Steptoe team to deliver impactful counsel to clients at the forefront of biotech innovation."
Steptoe's Intellectual Property group is recognized for its deep technical bench and strategic litigation and counseling capabilities across the US, Europe, and Asia. The team has been shortlisted and recognized by Chambers, Legal 500, World IP Review, LMG Life Sciences, and China Business Law Journal for its excellence in patent litigation, portfolio development, and cross-border IP strategy.
Yi earned her Ph.D. and M.S. in Molecular, Cellular, and Developmental Biology from Yale University. She holds a J.D. from Fordham University and a B.S. from Peking University. She is also registered before the United States Patent and Trademark Office.
About Steptoe
In more than 110 years of practice, Steptoe has earned an international reputation for vigorous representation of clients before governmental agencies, successful advocacy in litigation and arbitration, and creative and practical advice in structuring business transactions. Steptoe has more than 500 lawyers and other professional staff across offices in Beijing, Brussels, Chicago, Hong Kong, Houston, London, Los Angeles, New York, San Francisco, and Washington. For more information, visit www.steptoe.com.
