Photo of Fangli Chen

Dr. Fangli Chen is a partner in the Litigation Department and vice chair of the Life Sciences Patent Practice. She represents all types of companies in the biotech and pharmaceutical industries, and has deep scientific expertise and a strong business sense. Fangli effectively identifies and transforms technological developments into valuable intellectual property assets for her clients and specializes in the strategic development of complex IP portfolios for companies that align with their business goals.

Fangli’s practice also focuses on post-grant review before the USPTO, oppositions, pre-litigation and litigation strategy, due diligence investigations, freedom-to-operate, non-infringement and invalidity analysis, licensing and other IP matters in connection with commercial transactions. She handles a variety of technology areas including biochemistry, molecular and cell biology, immunotherapy, enzyme replacement therapy, messenger RNA therapy, gene therapy, vaccines, bioinformatics, and small molecule compound drugs.

Fangli also has a wealth of experience in the following areas:

  • Post-grant challenges: representing clients in inter partes review interference and various foreign opposition proceedings.
  • Technology transactions & licensing: advising clients on matters relating to technology or material transfer, licensing and research collaborations.
  • Investment or acquisition counsel: assisting investors in assessing the technology and intellectual property assets and risks for potential target investments and counseling companies on intellectual property matters in connection with public offering or acquisition.

Fangli has been repeatedly noted for her top-tier work by industry publications, including being listed as a World’s Leading Patent Practitioner by IAM Patent 1000 and recognized as one of the Top 250 Women in IP nationwide by Managing Intellectual Property. In 2019, she was named Patent Strategy & Management Attorney of the Year in Massachusetts by LMG Life Sciences. She has also been recognized by Best Lawyers in AmericaClient Choice, Legal 500Massachusetts Lawyers Weekly and Massachusetts Super Lawyers. Prior to joining Proskauer, Fangli was a partner at a leading Boston law firm.

In an unprecedented PTAB decision involving Spectrum Solutions LLC (“Spectrum”) (Petitioner) and Longhorn Vaccines & Diagnostics (“Longhorn”) (Patent Owner), the Board found all five challenged patents invalid and imposed sanction against patent owner Longhorn for failure to meet the duty of candor and fair dealing. The board determined that Longhorn selectively disclosed testing results to support its claim construction and misled its technical expert with incomplete laboratory data, thereby failed to meet its duty of candor and fair dealing in its actions before the Board. The claims and substitute claims in all five patents asserted by Longhorn were unpatentable due to its sanctionable misconduct. Longhorn was also ordered to provide Spectrum compensatory expenses including attorney fees. On one hand, it is a reminder that duty of candor is a continuing obligation that cannot be ignored even during the IPR proceeding.  On the other hand, it does raise the question whether the PTAB has the authority to invalidate a patent for misconduct. 

CRISPR patents continue to face priority challenges in Europe. Following an earlier revocation of CRISPR patent EP2771468 based on a successful priority challenge, another foundational CRISPR patent EP3241902, co-owned by University of California Berkeley (UCB), was revoked in its entirety last month by the European Patent Office (EPO) based on an invalid priority claim. This is the first significant loss of UCB’s CRISPR patent rights in Europe.