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 seventy patent matters 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 appeals at the Federal Circuit.


Honors & Awards

  • Recommended by The Legal 500 US for Patents: Litigation 
  • Recognized in Managing IP as a Managing Intellectual Property Rising Star (2022)
  • 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 Internet companies and consumer electronics company in three district court cases and related IPRs and reexaminations involving six patents directed to navigation and location technologies. (E.D. Tex.; N.D. Cal.; USPTO; Fed. Cir.) Secured stay pending reexaminations, invalidity of one patent, dismissal of second patent, and transfer of all three cases from E.D. Tex. to N.D. Cal.
  • Defended consumer electronics companies and display manufacturer in multiple lawsuits, including in the ITC, and related IPRs relating to OLED display technologies. (USITC; W.D. Tex.; E.D. Tex.; USPTO.) Litigated the ITC matter through an evidentiary hearing before resolving favorably on the eve of the initial determination.
  • Advised chip designer and manufacturer concerning ICC arbitration, licensing, and potential trade secret, contract, and copyright claims relating to 5G telecommunications technology.
  • Defended consumer electronics company in case relating to digital assistant and smart display devices. (W.D. Tex..) Took over as pretrial and trial counsel five months before trial, where the client prevailed on non-infringement and invalidity after an hour of deliberation.
  • Defended a consumer electronics company across seven actions and IPR proceedings covering twenty-three patents relating primarily to semiconductor fabrication. (E.D. Tex.; D. Del;  D.N.J.; USITC; USPTO.) Secured summary determination victory in the ITC and transfer of two E.D. Tex. cases to D. Del., after which, the matters settled favorably.
  • Defended Internet software company in a patent case relating to mapping software and technologies. (D. Del.; Fed. Cir.)  Took over as pretrial and trial counsel six months before trial, where we prevailed on behalf of our client against claims for an nine-figure judgment. The jury reached findings of non-infringement and invalidity based on two separate grounds after 30 minutes of deliberation. Led on post-trial and appeal briefing, where the jury verdict was upheld.
  • Defended an Internet and television provider against a patent monetization fund in a 19-patent case relating to digital subscriber line (DSL) technology. (W.D. Tex.) Secured case-dispositive victories at claim construction stage, including findings of indefiniteness, resulting in a favorable settlement.

Other Experience

  • Defending consumer electronics company in lawsuit relating to virtuality reality viewers. (N.D. Tex.)
  • Defending consumer electronics company in lawsuit relating to facial and gesture recognition features (E.D. Tex.)
  • Defending consumer electronics company in multiple lawsuits and related IPRs involving voice and digital assistant software and services.(W.D. Tex.; USPTO.)
  • Defending as trial and post-trial counsel an Internet software company in a patent case relating to web browsers, computer, and Internet security software.(E.D. Tex.)  Managed case through trial, post-trial and appeal.  In post-trial, prepared motion for new trial that was granted by the Court, vacating an unfavorable jury verdict.
  • Defended consumer electronics company in lawsuit relating to APIs for geo-location, taking over from prior counsel as pretrial and trial counsel three months before trial. (E.D. Tex.)  Matter settled favorably following key victories on summary judgment and Daubert motions.
  • Defended consumer electronics company in lawsuit relating to RF circuits and power amplifiers. (W.D. Tex.; USPTO)
  • Defended an Internet software company in a patent case relating to APIs for navigation software. (S.D. Cal.; W.D. Tex.)
  • Defended consumer electronics company in lawsuits relating to flash memory, electronics, and circuits. (W.D. Tex.; USPTO.)
  • Defended 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.)
  • Defended consumer electronics and software company in a ten-patent case spanning multiple technologies, including navigation. (E.D. Tex.)
  • Defended Internet company in patent case and related IPRs relating to image and facial recognition software. (E.D. Tex.; USPTO.)
  • Advised consumer electronics company on trade secret issues and clean room development procedures for future chip designs.
  • Defended Internet company in eleven patent case and related IPRs relating to video and audio streaming platforms (N.D. Cal.; USPTO.)
  • Defended a consumer electronics company in a nine-patent case relating to computer hardware and graphics processor technologies used in mobile devices. (E.D. Tex.)
  • Defended a consumer electronics company in a three patent case relating to memory chips, inter-chip communication protocols, mixed signal circuits, and related technology standards (E.D. Tex.)
  • Defended an Internet software company in a five patent case relating to image processing and navigation technologies (D. Del.)


Press Releases

In the News

IP Watchdog: Navigating the Customer-Suit Exception in Texas Courts

August 7, 2023

Law360: 3 Ways Courts Approach Patent Eligibility At Trial And After

July 19, 2023

Law360: Google Gets Fed. Circ. To Affirm PTAB’s Ax Of Mapping IP

July 12, 2023

The Recorder: Recent Trends in Federal Circuit Mandamus Addressing Transfer Motions Denied by Texas District Courts

April 25, 2023

Law360: Law360’s Legal Lions Of The Week April 21

April 21, 2023

Law360: Fed. Circ. Wipes Out Google’s US$20M Anti-Malware Patent Loss

April 17, 2023

Daily Journal: Promotions & Management

December 22, 2022

Global Legal Chronicle: O’Melveny to Add 11 New Partners in 2023

December 16, 2022

Law360: Post-Arctic Cat Lawsuits Reveal Patent Marking Pitfalls

August 9, 2022

The Texas Lawbook: Another Patent Infringement Defense Verdict in Waco in Win for Google

October 8, 2021

Law360: BREAKING: Google Didn’t Infringe Digital Photo Frame Patent, Jury Says

October 6, 2021

Law360: Google Owes Nearly $3M Over Photo Frame Patent, Jury Told

October 4, 2021

Alerts and Publications