Yun (Sophie) Wei, Ph.D. focuses her practice on patent litigation, specifically in the pharmaceutical, chemical, and biotechnology industries. Her experience covers a wide variety of therapeutic areas, including diabetes, multiple sclerosis, stomach ulcers, gastroesophageal reflux disease, hypertension, stroke, cholesterol, chemotherapy, inflammation, and pain management.


  • Washington University School of Law (J.D.)
  • Texas A&M University (Ph.D.)
    • Biochemistry
  • Wuhan University (B.S.)
    • Biotechnology

Bar Admissions

  • Illinois
  • Georgia
  • U.S. Court of Appeals, Federal Circuit
  • U.S. District Court, Southern District of Indiana
  • U.S. District Court, Western District of Michigan
  • U.S. Patent and Trademark Office

Representative Experience

  • Represented clients in Hatch-Waxman (ANDA) patent litigations relating to various drug products including lansoprazole, dalfampridine, linagliptin, carvedilol, saxagliptin, and diclofenac sodium.
  • Represented pro bono in an appeal to the U.S. Court of Appeals for the Federal Circuit involving a claim for veterans’ benefits and served as second chair in oral argument in the appeal.
  • Participated in copyright and patent infringement cases involving mobile phones, medical devices, and software.

Background and Credentials

Prior to joining Marshall, Gerstein & Borun LLP, Dr. Wei represented clients in Hatch-Waxman litigations relating to drug and pipeline products. Dr. Wei also advised clients on the pre-litigation and regulatory strategy for obtaining approval for pharmaceutical and biological products, including matters related to the Orange Book, drug product exclusivities, abbreviated new drug applications (ANDA) and 505(b)(2) new drug applications (NDA) pathway. In addition, she participated in copyright and patent infringement cases involving biotech, medical devices, and software. She also has experience in prosecuting patent applications, providing opinions regarding validity, infringement and freedom-to-operate issues, and advising clients on due diligence issues related to potential investments and business transfer.

She received her J.D. from Washington University School of Law, where she was a recipient of the Scholar in Law Award and served as an Executive Articles Editor for Washington University Global Studies Law Review. She holds a Ph.D. in biochemistry from Texas A&M University, as well as a B.S. in biotechnology from Wuhan University in China. Prior to practicing law, she researched problems of interest to the pharmaceutical industry, including mechanisms related to autoimmune diseases and Alzheimer’s diseases.

Dr. Wei speaks fluent Mandarin Chinese.

Publications and Presentations

  • “Experimental and Computational Studies on Protein Folding, Misfolding and Stability,” Dissertation, 2009.
  • “NMR study and molecular dynamics simulations of optimized β-hairpin fragments of protein G,” Proteins, 2007.
  • “A preliminary study of the karyotype of Gobiocypris Rarus,” Acta Hydrobiologica Sinica, 2001.

Community and Professional Involvement

  • Federal Circuit Bar Association – Member
  • American Bar Association – Member
  • Intellectual Property Law Association of Chicago (IPLAC) – Member