Image: Phillip W. Citroen

Phillip W. Citroen

Partner, Litigation Department


Phillip Citroën is an intellectual property partner in the Litigation department in the firm’s Washington, D.C. office.

Mr. Citroën is a registered patent attorney practicing all aspects of patent-related work, including litigation before U.S. district courts and the U.S. International Trade Commission (ITC), post-grant proceedings before the Patent Trial and Appeal Board (PTAB) of the U.S. Patent and Trademark Office (USPTO), and appeals before the Federal Circuit. Mr. Citroën has represented petitioners and patent owners in over 100 post-grant proceedings, including inter partes review (IPR) and post-grant review (PGR) proceedings. In many instances, Mr. Citroën’s involvement in these proceedings has been coupled with parallel district court or ITC litigation.

Mr. Citroën’s litigation experience spans all stages of litigation, including fact and expert discovery, motion practice, claim construction, and trial. Mr. Citroen’s experience also includes oral argument before the Court of Appeals for the Federal Circuit.

Mr. Citroën has been recognized for his work in the area of patent law. The National Law Journal has recognized Mr. Citroën as one of the D.C. region’s 40 most promising lawyers age 40 and under. Managing IP has recognized Mr. Citroën as a “Rising Star.” And Intellectual Asset Management has recognized Mr. Citroën in its IAM Patent 1000. Additionally, Law360 has recognized Mr. Citroën as a "Legal Lion" for several significant victories.

Mr. Citroën has also gained valuable experience as in-house patent counsel for a Fortune 500 company that provides information infrastructure solutions.


  • Intellectual Property: Patents: Prosecution, The Legal 500 US
  • Rising Star (D.C. Region’s Top 40 Age 40 and Under), The National Law Journal
  • IAM Patent 1000, Intellectual Asset Management
  • Rising Star, Managing IP
  • Legal Lion, Law360


  • George Washington University Law School, J.D., 2010
  • Virginia Tech, B.S., Computer Science, 2007 (cum laude)


  • Representation of various companies, including Google, Samsung, Uber, eBay, PayPal, Helsinn, Walgreen, Mitek, JSR, Everspin, and VoltServer in IPR, PGR, and CBM proceedings before the PTAB and appeals from these proceedings to the Federal Circuit.
  • Elm 3DS Innovations, LLC v. Samsung Electronics Co., Ltd. (D. Del.). Representation of Samsung in a patent infringement case, IPRs and Federal Circuit appeals involving 3D semiconductor technology.
  • EIS, Inc. v. WOW Tech International GmbH (D. Del.). Representing EIS in an unfair competition and patent infringement case involving personal health products.
  • Certain Pneumatic Compression Devices and Components Thereof, 337-TA-1316 (ITC) & Innovamed Health LLC v. ManaMed Inc. (E.D. Tex.). Representation of Innovamed in patent infringement cases involving portable compression devices.
  • Scanton Technologies, LLC v. Everspin Technologies, Inc. (W.D. Tex.). Representation of Everspin in patent infringement case involving memory products.
  • Advanced Marketing Systems, LLC v. Walgreen Co. (E.D. Tex.). Representation of Walgreen in a patent infringement case, CBMs, and Federal Circuit appeals involving electronic couponing technology.
  • Rothschild Mobile Imaging Innovations, LLC v. Mitek Systems, Inc. (D. Del.). Representation of Mitek in a patent infringement case and IPRs involving software.
  • Certain Digital Media Devices, Including Televisions, Blu-Ray Disc Players, Home Theater Systems, Tablets and Mobile Phones, Components Thereof and Associated Software, 337-TA-882 (ITC). Represented LG in a patent infringement case involving digital media technology and location-based services technology.
  • Audiovisual Components and Products Containing the Same, 337-TA-837 (ITC). Represented Realtek in a patent infringement case involving wireless technology.
  • Bear Creek Technologies, Inc. v. Verizon Services Corp. (E.D. Va.). Represented Verizon in a patent infringement case involving Voice over Internet Protocol (VoIP) technology.
  • Certain Semiconductor Chips and Products Containing the Same, 337-TA-753 (ITC). Represented Rambus in a patent infringement case involving semiconductor devices.

    Engagement & Publications

    • Speaker, 4th Annual Berkeley-Tsinghua Conference on Transnational IP Litigation, Berkeley School of Law, June 13, 2022.
    • Quoted, "PTAB Says Amendments Still Rare, But Data Is Incomplete," Law360, July 16, 2020.
    • Speaker, "The Rise of PTAB Discretionary Denials," IPWatchdog, May 21, 2020.
    • Guest Lecturer on Post-Grant Proceedings Under the AIA, New York University Law School, April 23, 2019.
    • Speaker, Electronic Discovery – Learn It, Love It, Live It!, AIPLA Annual Meeting, Washington, D.C., October 26, 2018.
    • Speaker, Briefing and Arguing IP Cases, Student Intellectual Property Law Association, The George Washington University Law School, Washington, D.C., January 31, 2018.
    • Quoted, "4 Recent PTAB Decisions Attys Need To Know," Law360, October 22, 2018.
    • Coauthor, "USPTO Proposes Changing Claim Construction Standard for IPRs, PGRs, and CBMs," Lexology, May 10, 2018.
    • Quoted, "PTAB Gives Hope for Patent Amendments Amid Reform Talk," Law360, April 2, 2018.
    • Quoted, "After Lesson in Procedure, Federal Circuit May Mop Up AIA Issues," Law360, February 12, 2018.
    • Coauthor, "Aqua Products: Watershed Decision or Barely a Ripple," Law360, October 16, 2017.
    • Coauthor of various publications for the Federal Circuit Bar Association's Circuit Case Digest.


    • PTAB Bar Association: Vice-Chair, Membership Committee (2018-Present)
    • American Bar Association: Editorial Board, Landslide® magazine (2018-Present)
    • American Intellectual Property Law Association

    Practice Areas


    Patent Office

    Patent Litigation

    ITC Section 337 Investigations

    Intellectual Property




    District of Columbia Bar

    Massachusetts Bar


    The George Washington University Law School, J.D. 2010

    Virginia Polytechnic Institute and State University, B.S. 2007

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