Knobbe/Martens: Intellectual Property Law
I never lose sight of what my clients consider a win.

Karen Vogel Weil


At a Glance

  • J.D. The George Washington University Law School
  • B.A. History, University of California - Davis

  • State Bar of California
  • Supreme Court of the United States
  • U.S. Court of Appeals for the Federal Circuit
  • U.S. Court of International Trade
  • U.S. District Court - Central District of California
  • U.S. District Court - Northern District of California
  • U.S. District Court - Southern District of California

Professional Profile 

Intellectual property litigator and trial attorney Karen Vogel Weil represents plaintiffs and defendants in complex, high-stakes patent, trademark, copyright and trade secret disputes. Karen is a highly experienced, relentlessly driven and proven advocate both in and out of court. In an era where few litigators actually go to trial, Karen has tried more than a dozen cases.

Whether through favorable settlement, fighting aggressively in litigation, developing the right trial strategy, or identifying any other opportunity that can be seized for a favorable outcome, Karen focuses on realizing positive results for all of her clients. Karen thrives under the constant challenge of finding creative solutions and developing winning strategies. Karen’s in-depth knowledge of the law, credibility and positive presence allow her to establish immediate rapport and credibility with judges and juries alike.

Karen has well-recognized expertise in the area of patent damages. Notably, she spearheaded the damages portion of two significant lawsuits, including at trial, for long-time firm client, Masimo Corporation. In the first trial against Masimo’s major rival, a jury awarded Masimo over $134 million. That victory allowed Masimo to settle the dispute, develop a significant market presence, go public, and generate hundreds of millions of dollars in ongoing royalties. In the second trial, against another major rival, the jury awarded over $466 million — the largest IP award of the year. After the district court upheld the jury’s verdict, the parties settled their dispute and entered a business deal worth hundreds of millions of dollars. On behalf of accused infringers, Karen has succeeded in obtaining judgments of no damages, despite a verdict of liability. Particularly because of her undeniable skill, hands-on experience and time-tested experience relating to patent damages, Karen is sought after to serve on litigation and trial teams by clients and colleagues alike, who depend on her regarding their most critical disputes.

Listed multiple times in Southern California Super Lawyers magazine, Karen is among the publication’s “Top Women Attorneys in Southern California” and included in the “Corporate Counsel” edition. She is also among the Los Angeles Business Journal’s "Leaders in Law,” The Best Lawyers in America, Intellectual Asset Management (IAM) magazine’s “Patent 1000 World's Leading Patent Professionals,” and an American Lawyer “Top Rated Lawyer in Intellectual Property Law.”

Active in the community, Karen serves in leadership positions in a variety of legal and other professional associations. Karen is frequently invited to speak on patent litigation matters and, in particular, on damages-related issues.


  • The George Washington University Law School (J.D. 1984), with honors, Member - George Washington Journal of International Law & Economics
  • University of California - Davis (B.A. History 1980), cum laude, Phi Beta Kappa Honorary Society
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