Louis Tompros

Louis Tompros is an experienced first-chair trial and appellate litigator. He makes the fast-moving and legally complicated field of intellectual property understandable for juries and judges. He has handled the most challenging patent, trademark, copyright, trade dress, publicity, and defamation matters at trial and on appeal, for high profile clients in technology, entertainment, artificial intelligence, and alternative energy, and he has been hailed as a “prizefighter” in the world of intellectual property litigation. He has successfully tried numerous intellectual property cases to verdict as lead trial counsel, has successfully argued multiple appeals before federal circuit courts, and teaches both Patent Law and Patent Trial Advocacy at Harvard, where he holds the title of Hieken Lecturer in Patent Law.

In the patent space, Mr. Tompros has handled cases involving artificial intelligence, smartphones, semiconductors, alternative energy, powersports vehicles, DNA testing, power conversion, data encryption, video compression and plastic storage devices. In 2026, he represented technology companies securing a first-of-its-kind defense verdict of patent noninfringement and license at trial in the Eastern District of Texas and earning a “Litigator of the Week” shout-out from The American Lawyer. In 2022, he was lead trial counsel for a defendant in a case resulting the invalidation of a competitor’s asserted alternative energy patent, and in 2021, he successfully argued a summary judgment motion resulting in the elimination of more than $5 billion of a patent plaintiff’s damages claim. He has likewise prevailed in multiple inter partes review and reexamination proceedings before the Patent Trial and Appeal Board. And in the patent, trade-secret, and copyright spaces, he has represented AI companies in litigation at the forefront of developing technological disputes, including fair use in AI training, prompt-injection hacking, copyrightability, and complex patent infringement litigation.

Among Mr. Tompros’ first-chair trial successes in his representation of Bombardier Recreational Products, in which a federal jury returned a full defense verdict rejecting a $130 million trademark infringement claim brought by Jaguar Land Rover over its “Defender” trademark. Land Rover had previously won a similar case against BRP in the European Union, making this US jury trial win particularly significant, and earning Mr. Tompros the title of “Litigator of the Week” from The American Lawyer. In 2021, he secured a high-profile victory for recording artist Elizabeth Chan over singer Mariah Carey, in which the Trademark Trial and Appeal Board permanently rejected Carey’s attempt to register the trademark “Queen of Christmas.” The win resulted in widespread industry and media praise, including coverage in the New York Times, the Wall Street Journal, Variety, and People. And in 2025, he secured another high-profile trademark victory for conceptual artist Ryder Ripps in the first Ninth Circuit appeal addressing intellectual property for cryptographic blockchain non-fungible tokens, earning him another American Lawyer “Litigator of the Week” shout-out and ranking as one of Law360’s top trademark cases of 2025.

Mr. Tompros also represents artificial intelligence platforms, visual and conceptual artists, filmmakers, agencies, video game publishers, authors and celebrities in copyright infringement and related actions, including the creator of the famous “Pepe the Frog” comic book character in enforcement efforts to reclaim the character from “alt-right” entities. His successful copyright enforcement action against Alex Jones’ Infowars media platform was named one of the top copyright rulings of the year by Law360, and is the subject of the Emmy-winning and Sundance prize-winning documentary Feels Good Man. In 2024, he represented software company DesignwarePro in a complex international copyright and trade secret arbitration, resulting in complete victory including an award of attorneys’ fees. He has also represented clients in defamation, trade dress, unfair competition, and design patent matters in courts throughout the country, and is frequently cited as an authority in the application of intellectual property law to evolving internet phenomena, including artificial intelligence, memes, deepfakes and NFTs.

As an appellate lawyer, Mr. Tompros regularly appears before the United States Court of Appeals. His Federal Circuit advocacy as lead counsel in (among other cases) Arctic Cat Inc. v. Bombardier Recreational Products Inc., In re Klein, and In re Packard has shaped the patent law. The Klein case, for example, resulted the Patent Office issuing a public agency-wide memo instructing all patent examiners on new rules for patent examination.

Pro bono representation is also an important part of Mr. Tompros’ practice. He represents civil rights icon James Meredith in a complex trademark dispute with the University of Mississippi, and previously represented Save the Children in its trademark enforcement activity against members of the “QAnon” movement. He has represented artists, authors, and a prominent literary journal on a pro bono basis in copyright and intellectual property contract matters, including representations through the Volunteer Lawyers for the Arts. He has represented terminated employees in unemployment insurance claims and appeals, public housing tenants facing eviction, and public advocacy groups submitting amicus briefs on criminal defense and privacy issues. In one of his early cases, Mr. Tompros represented a group of gay and lesbian service members challenging the constitutionality of the military’s “Don’t Ask, Don’t Tell” policy, in association with the Servicemembers Legal Defense Network.

While attending Harvard Law School, Mr. Tompros was Supreme Court Chair of the Harvard Law Review and a member of the winning team in the Ames Moot Court Competition.