Mark Liang


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Mark Liang focuses his legal practice on patent and technology-related litigation. He has experience in all stages of patent cases, including claim construction, fact and expert discovery, dispositive motions, trial, post-trial, and appeal. He represents clients in federal courts, the International Trade Commission, and United States Patent and Trademark Office, including reexaminations and inter partes review (IPR). He has litigated over sixty patent cases in district courts, five ITC investigations, and over forty IPRs. He has been on several successful trial teams, including in the Eastern District of Texas, Western District of Texas, District of Delaware, and the International Trade Commission, and has also served as lead counsel for clients in IPR proceedings. He has argued at dozens of hearings on claim construction and dispositive motions, and also taken/defended several dozen depositions, including of expert witnesses, inventors, and corporate fact witnesses. He has also briefed and argued appeals at the Federal Circuit.

Mark has a background in electrical engineering, and he leverages his expertise to assist clients across a number of technical fields, including telecommunications, signal processing, multimedia, computer graphics, computer hardware, electronics, internet technologies, display technologies, and semiconductor fabrication. He focuses his practice on the largest and most contentious patent litigation matters, particularly the most technically challenging cases. He also handles trade secret matters and advises on software copyright and technology standards matters, including F/RAND damages and obligations to standards setting organizations. His clients and matters span a variety of fields in the technology sector, including Internet, consumer electronics, mobile devices, telecommunications providers, chip designers and manufacturers, display manufacturers, and telecommunications equipment manufacturers. He has received industry recognition, including being identified as a Rising Star by Managing IP and as a noted and recommended patent litigation practitioner by The Legal 500.

Honors & Awards

  • Recommended by The Legal 500 US for Patents: Litigation (2022)
  • Recognized in Managing IP as a Managing Intellectual Property Rising Star
  • Recognized in California Super Lawyers, Intellectual Property


Bar Admissions

  • California

Court Admissions

  • US District Court, Northern, Central, and Southern Districts of California
  • US Federal Circuit Court of Appeal

Registered to Practice

  • US Patent and Trademark Office


  • University of Chicago, J.D.: with honors; John M. Olin Fellowship in Law and Economics; Executive Editor, The Chicago Journal of International Law
  • University of Toronto, B.A.Sc., Electrical Engineering: with high distinction

Professional Activities


  • Seventh Circuit Court of Appeals 


  • Bar Association of San Francisco 
  • American Intellectual Property Law Association (AIPLA), Editorial Board member, AIPLA Quarterly Journal
  • Asian American Bar Association Bay Area (AABABA)


  • “Post-Arctic Cat Lawsuits Reveal Patent Marking Pitfalls,” Law360 (August 9, 2022)
  • “Fee Shifting in Patent Litigation,” (co-author Brian Berliner), Virginia Journal of Law & Technology, Vol.18, No.01 (Fall 2013)
  • “Chinese Patent Quality:  Running the Numbers and Possible Remedies,” 11 J. Marshall Rev. Intell. Prop. L. 478 (2012)
  • “The Aftermath of TS Tech:  The End of Forum Shopping in Patent Litigation and Implications for Non-Practicing,” 19 Texas Intell. Prop. L. J. 29 (2010)
  • “Stopping Intellectual Property Infringement in China:  A Three-Pronged Approach,” 11 Chi. J. Int’l. L. 285 (2010)
  • “Green Taxes and the WTO: Creating Certainty for the Future,” 10 Chi. J. Int’l. L. 359 (2009)


  • “Quality of Chinese Patents,” Review of Intellectual Property Law Symposium (Chicago, April 2012)
  • “Popular Districts for Patent Cases,” Berkeley Law Series (Berkeley, February 2012)  
  • Defending consumer electronics company in lawsuit relating to virtuality reality viewers. (N.D. Tex.)
  • Defending consumer electronics company in lawsuit relating to RF circuits and power amplifiers. (W.D. Tex.; USPTO)
  • Defending consumer electronics company in lawsuits relating to flash memory, electronics, and circuits. (W.D. Tex.; USPTO.)
  • Defending consumer electronics companies and display manufacturer in multiple lawsuits and related IPRs relating to OLED display technologies. (USITC; W.D. Tex.; E.D. Tex.; USPTO.)
  • Defending an Internet software company in a patent case relating to APIs for navigation software. (S.D. Cal.; W.D. Tex.)
  • Advising chip designer and manufacturer concerning ICC arbitration, licensing, and potential trade secret, contract, and copyright claims relating to 5G telecommunications technology.
  • Defending consumer electronics company in multiple lawsuits and related IPRs relating to smartphone hardware components, including flash memory, RF receivers/modems, and processors. (E.D. Tex.; W.D. Tex.; N.D. Cal.; USPTO.)
  • Defending Internet companies and consumer electronics company in three related cases and related IPRs and reexaminations involving six patents relating to navigation and location technologies. (E.D. Tex.; N.D. Cal.; USPTO; Fed. Cir.)
  • Defending consumer electronics company in multiple lawsuits and related IPRs involving voice and digital assistant software and services. (W.D. Tex.; USPTO.)