Overview
Doug Wentzel focuses his practice on patent and trade secret litigation. Doug successfully represents clients in district courts across the country and before the International Trade Commission (ITC), Patent Trial and Appeal Board (PTAB), and Patent Office. Doug is adept at understanding complex technologies and has assisted clients in cases covering a broad spectrum of technologies, including wearable health devices, minimally invasive heart repair devices, respiratory therapy products, automotive shock absorbers, microdermabrasion systems, and more. Doug also has experience litigating design patents.
Among other client successes, Doug played an integral role in a high-profile ITC investigation resulting in an import ban of the Apple Watch, and in persuading both the PTAB and the Patent Office not to institute challenges to the patents underlying the import ban.
Doug is actively involved in the legal community and is a co-chair of the Young Lawyers Division of the Federal Bar Association’s Orange County Chapter.
Education
- University of Pennsylvania Law School (J.D., 2016), cum laude
- Drexel University (B.S. Civil Engineering, 2013), summa cum laude
Representative Experience
Masimo Corp. et al. v. Apple Inc. (C.D. Cal.)
Doug Wentzel is a core member of the Knobbe Martens team representing Masimo and Cercacor Laboratories against Apple in various forums. Mr. Wentzel is deeply involved in handling Masimo’s patent liability and technical trade secret claims in a case pending in the Central District of California. After a November 2025 trial, the jury found Apple infringed Masimo’s patent and awarded more than $634 million in damages.
Apple Inc. v. Masimo Corp. et al. (D. Del)
Mr. Wentzel is a key member of the Knobbe Martens team representing Masimo in a case pending in the District of Delaware, where Masimo asserts patent infringement, antitrust, and false advertising claims against Apple.
Apple Inc. v. Masimo Corp. (USPTO)
Successfully defended Masimo against Apple’s six petitions for inter partes review of the Masimo pulse oximetry patents that formed the basis of the ITC exclusion order banning the import of certain Apple watches. The Patent Office declined to institute all six IPR petitions.
In re Certain Light-Based Physiological Measurement Devices and Components Thereof (ITC)
Successfully represented Masimo against Apple in ITC investigation relating to infringement of Masimo’s patented pulse oximetry technology. Obtained exclusion order and cease and desist order banning Apple from importing and selling certain Apple Watches.
Fisher & Paykel Healthcare Ltd. v. Flexicare Inc. (C.D. Cal.)
Successfully represented Fisher & Paykel Healthcare in asserting multiple patents relating to respiratory care products. Obtained summary judgment of patent infringement. Achieved favorable case-dispositive settlement before trial.
: In re Certain Sleep Disordered Breathing Treatment Systems and Components Thereof (ITC)
Successfully represented Fisher & Paykel Healthcare in ITC investigation relating to alleged infringement of patents on patient interfaces for sleep apnea therapy. After obtaining a favorable evidentiary ruling for Fisher & Paykel Healthcare, patentee unilaterally withdrew its complaint and terminated the investigation.
Recognition
Awards & Honors
- Recognized in Best Lawyers: Ones to Watch for Intellectual Property Litigation, Patent Litigation, and Patent Law (2025-2026)
- Named to Benchmark Litigation’s “40 & Under” List (2026)
- Recognized as a Rising Star in Managing IP‘s “IP Stars” guide (2023-2026)
News & Insights
Articles
Co-author, “35 U.S.C. § 325(d) Petition Practice in Ex Parte Reexaminations,” Reuters Westlaw, October 2024.
Co-author, “Tips for Patent Prosecutors from Litigators: Enhancing Litigation Outcomes,” IP Watchdog, August 2024.
Stays Pending Inter Partes Review: Not in the Eastern District of Texas, 98 J. Pat. & Trademark Off. Soc’y 120 (2016)
Uber & Alice: Could One Patent Really Take Down this Ridesharing Giant?, 98 J. Pat. & Trademark Off. Soc’y 86 (2016)
Editor and Contributor, Knobbe Martens Litigation Blog
Editor, KnobbeMedical.com Blog
