Tianran Yan is a partner and intellectual property lawyer in the Washington, D.C. office of Foley & Lardner LLP. He has extensive experience in assisting clients with worldwide patent and trade secret protection strategies. His practice focuses on patent prosecution and counseling, due diligence investigation, patent portfolio management, patent enforcement and licensing, freedom-to-operate investigation and patent validity and infringement analyses.

Tianran is a member of the firm’s Chemical, Biotechnology & Pharmaceutical Practice Group and the Life Sciences Industry Team. He has represented clients in a broad spectrum of technologies, including CRISPR genome editing, liquid biopsy, next-generation sequencing (NGS), bispecific and multispecific antibodies, proteolysis targeting chimeras (PROTACs), single-cell sequencing and analysis, ex vivo and in vivo cell engineering and regenerative medicine.

One particular area of Tianran’s patent practice is post-grant proceedings. He has successfully represented clients in patent reexamination, reissue and inter partes review (IPR) proceedings.

Tianran has also represented clients in IP due diligence investigation of technology companies. He has performed due diligence reviews for IP licenses, IP portfolio sales, corporate financing, investments, mergers and acquisitions. Tianran has co-authored Due Diligence for Intellectual Property: Valuing Assets in a Transaction, Chapter 2: Patents (Law Journal Press, 2014).

Tianran has extensive experience counseling Chinese technology companies on strategic IP development and transactions in connection with their operation in the U.S. market. Tianran is a native speaker of Mandarin.


Tianran has been recognized as a Next Generation Lawyer for patent prosecution (including re-examination and post-grant proceedings) by The Legal 500, which notes the top up-and-coming lawyers nationwide.


Tianran earned his law degree from the Chicago-Kent College of Law (J.D., 2009), where he was an editor of the Chicago-Kent Law Review. Tianran earned his master’s degree in biochemistry (M.S., 2006) from University of Illinois at Chicago, College of Medicine, and his bachelor’s degree (B.S., 2004) from Sun Yat-Sen University.


Tianran is admitted to practice in Illinois and the District of Columbia and before the U.S. Patent and Trademark Office.

Select Publications and Presentations

  • Chapter co-author, “Due Diligence for Intellectual Property: Valuing Assets in a Transaction,” Law Journal Press (2014)
  • Co-author, “IPR: How to Gain a Tactical Advantage,” World Intellectual Property Review (March 9, 2016)
  • Co-author, “IPR Proactive Defense Measures – Strategies and Considerations for Patent Owners,” PTAB Trial Insights (May 31, 2016)
  • Co-author, “Data analysis: the highs and lows of generic-filed IPRs,” Life Sciences Intellectual Property Review (August 30, 2017)
  • “Navigating the CRISPR Patent Landscape and Business Impact,” Era-Defining Life Sciences Technologies web conference (June 24, 2016)
  • “Healthcare & Biotechnology,” 2016 US-China Innovation and Investment Summit (May 17, 2016)