Areas of Practice
  • Cantonese
  • Mandarin
  • Fordham University Law School, JD, cum laude, Order of the Coif, The Senior Prize, 2002
  • Harvard University, Ph.D, Immunology, 1996
  • Smith College, BA, magna cum laude, with Highest Honors in Biochemistry, 1990
Bar & Court Admissions
  • New York
  • US Court of Appeals for the Federal Circuit
  • US District Court for the Eastern District of New York
  • US District Court for the Southern District of New York
  • US Patent and Trademark Office

Z. Ying Li, Ph.D.

1114 Avenue of the Americas
New York NY 10036
TEL: +1 212 506 3912
FAX: +1 212 506 3950

Z. Ying Li, Ph.D., a partner in Steptoe's New York office, counsels biotechnology and pharmaceutical clients on patent portfolio management and strategic development.  She has extensive experience in patent prosecution worldwide.  Dr. Li helps clients survey competitive patent landscapes and renders opinions of counsel on freedom to operate, non-infringement, and patent invalidity.  She also conducts IP due diligence for venture capital investment and corporate business development. 

Dr. Li has worked on a wide range of therapeutic areas including cancer and immune disorders, with particular experience in biologics such as antibody therapeutics, as well as molecular diagnostics and vaccines.  She assists clients with pre-litigation strategy counseling and freedom to operate analyses concerning application of the Biologics Act to biotherapeutic development programs.   

Dr. Li also has extensive experience in contentious matters before US and foreign patent offices, and has represented clients in matters related to transgenic animals and immune molecules.  She successfully argued for an interference appellee before the Court of Appeals for the Federal Circuit in a case of first impression related to conception of recombinant DNA. 

During her doctoral research, Dr. Li discovered a novel gene involved in DNA double-stranded break repair and antibody gene rearrangement.

Select News & Events

  • European Patent Office Perspectives on Life Sciences Patent Examination, September 28, 2017, A Steptoe-sponsored event
  • Speaker, “Patent Portfolio Management in Light of Life Techs. v. Promega and Extraterritorial Reach of U.S. Patents,” 8th Annual Summit on Biosimilars, American Conference Institute, 2017
  • Speaker, “Immunotherapy: a Patent Perspective,” World Gene Congress, Shanghai, 2016
  • Steptoe Further Expands IP, Biologics Practice with Ying Li in New York
  • Speaker, “Biosimilars: A Patent Perspective,” Licensing Executives Society of New Jersey, October 2015
  • Speaker, “Patent Prosecution from a US Perspective,” Munich, the European Patent Office, March 2012
  • Panelist, “Mayo v. Prometheus and Its Implications in the Biotech Industry,” New York Intellectual Property Law Association Forum, 2012

Selected Publications

  • September 29, 2017, Bloomberg BNA’s Life Sciences Law & Industry Report
  • Co-author, “Patents: a Tool to Bring Innovation from the Lab Bench to the Marketplace," chap. 18 in Yeast Metabolic Engineering: Methods and Protocols (Methods in Molecular Biology Series), ed. V. Mapelli (Humana Press, 2014)