Peter Klepacz represents clients – from early-stage start-ups to multinational corporations – in patent, trademark, copyright, and complex commercial disputes. He brings a hands-on approach to IP litigation strategy, portfolio development, licensing, and freedom-to-operate, noninfringement, and third-party rights analyses. Peter has industry experience spanning pharmaceuticals, diagnostics, medical devices, research tools, sporting goods, cosmetics, and fashion. Since joining Wilson Elser, he has also expanded his practice into aviation law, drawing on his technical background in the sciences.
Peter handles all phases of litigation, from early case strategy and discovery through dispositive motions and trial preparation. He has litigated high-stakes matters in federal courts across the country and before the Patent Trial and Appeal Board (PTAB) and Trademark Trial and Appeal Board (TTAB), including disputes valued in the hundreds of millions of dollars. His background as a former patent prosecutor enables him to understand the patents he litigates from the inside out.
Before joining Wilson Elser, Peter was an associate at an AmLaw 150 firm, where he led discovery and served on trial teams across a wide range of IP and commercial matters. Before that, he worked as a patent prosecution and litigation associate at a boutique IP firm. During law school, Peter served as a judicial intern at the Wisconsin Supreme Court, grounding his practice in rigorous appellate analysis.
A proud first-generation Polish American, Peter is fluent in Polish.
Areas of Focus
Intellectual Property
Peter brings a distinctive combination of patent prosecution and litigation experience to his IP practice. Having drafted and prosecuted patent applications himself, he has a technical understanding of patent claims that bolsters his litigation work, from claim construction and prior art analysis to expert development and dispositive motions. His practice also encompasses trademark enforcement and opposition proceedings, trade secret misappropriation, and copyright disputes. Peter has litigated high-stakes matters in federal courts and before the PTAB and TTAB across industries including pharmaceuticals, medical devices, aviation, and consumer products. That experience, paired with his biochemistry background, allows him to comprehensively protect clients’ intellectual property.
Commercial Litigation
Peter represents clients in complex business disputes, including breach of contract, fraud, breach of fiduciary duty, unfair business practices, and partnership disputes. His experience managing discovery, developing case strategy, and preparing matters for trial in federal and state courts translates across subject areas. Whether defending a class action, litigating a commercial lease dispute, or enforcing a multimillion-dollar judgment, Peter brings the same analytical rigor and strategic focus that defines his IP work.
Aviation
Since joining Wilson Elser, Peter has expanded his practice into aviation law, leveraging his technical fluency and proven ability to quickly master complex subject matter. His experience managing high-stakes litigation and working closely with technical experts makes him well positioned to handle the unique challenges of aviation disputes, where understanding intricate systems and regulatory frameworks is essential.
- Marquette University Law School (J.D., magna cum laude, 2020)
- Managing Editor, Marquette Intellectual Property Law Review
- Web Editor, Marquette Law Review
- University of Wisconsin–Madison (B.S. Biochemistry and Polish, 2016)
- Certificate in Global Health
- California
- Wisconsin
- U.S. Patent & Trademark Office
- U.S. District Court, Eastern District of Wisconsin
- Polish