Overview
Brian Claassen leverages his legal experience and deep technical aptitude to successfully resolve high-stakes technology disputes. Clients trust Brian to present their most critical disputes in both jury and bench trials. He has protected his clients’ valuable patents and trade secrets through litigation, including obtaining significant jury verdicts, exclusion orders, and preliminary and permanent injunctions. Brian navigates the most complex issues with poise at the lectern. In November 2025, Brian led a team that obtained a $634M jury verdict on behalf of Masimo Corporation.
Brian develops clear strategic guidance that leads his clients to success in district court, the International Trade Commission (ITC), the Patent Trial and Appeal Board (PTAB), and appeals. Brian’s litigation victories have resulted in significant jury verdicts, exclusion orders from the ITC, injunctions in federal courts, and multiple defense victories. On two separate occasions, Brian has persuaded the PTAB not to institute six separate petitions challenging his clients’ patents. Brian has also invalidated dozens of patents, including those purporting to cover industry standards.
Clients rely on Brian to master and present their most technically complex matters. Brian has presented and cross-examined more than twenty fact and expert witnesses at jury and bench trials. Brian’s technical experience in electronic product design, including digital and analog hardware, signal processing, firmware and software development, helps him immediately understand his clients’ most complex technical issues. Brian has protected his client’s leading technology in industries including noninvasive monitoring, cellular phones, robotics, and semiconductors. Brian has also successfully challenged patents purporting to cover USB, side-curtain airbags, signal processing, and magnetic resonance imaging. Brian’s electrical engineering background gives him the ability to master wide-ranging technologies, such as wireless communications, signal processing, medical devices, automative electronics, semiconductors, consumer electronics, and digital and analog circuitry.
Brian is an active leader of the bar and an involved member of the California legal community. He is a founding member and served in numerous positions with the Howard T. Markey Intellectual Property Inn of Court, including currently as President-Elect. He also served as President of the Federal Bar Association Orange County Chapter. A leader within Knobbe Martens as well, Brian co-chairs the firm’s electrical, semiconductor & computer technology litigation committee. He also serves on the firm’s pro bono and litigation committees and is past chair of the firm’s mentor committee. Brian has been recognized by leading intellectual property publications for his outstanding work in intellectual property litigation.
Before joining the firm, Brian developed embedded systems and signal processing devices as a Senior Software and Hardware Engineer at QSC Audio Products.
Education
- University of Notre Dame Law School (J.D., 2007), Intellectual Property Summer Institute, Tsinghua University, Beijing, China (2005)
- Vanderbilt University (B.E. Electrical Engineering, 1998)
Representative Matters
Masimo Corp. et al. v. Apple, Inc., Case No. 8:20-00048 (C.D. Cal.)
Brian Claassen co-leads the Knobbe Martens team representing two related companies (Masimo and Cercacor Laboratories) against Apple in several forums. Mr. Claassen manages the patent liability and technical trade secrets in a case pending in the Central District of California. Following a November 2025 trial, the jury returned a verdict of over $634M in favor of Masimo.
Masimo Corp. et al. v. True Wearables, Inc., Case No. 8:18-cv-02001 (C.D. Cal.), aff’d, 2022 WL 205485 (Fed. Cir. 2022)
Mr. Claassen examined witnesses and made closing arguments on behalf of Masimo in a trade secret misappropriation case against a former executive. The case centered around the former Chief Technical Officer of Cercacor, charged with leading research and development using Masimo’s core technologies. That executive left the Masimo affiliate and later launched his own company True Wearables.
The team obtained a preliminary injunction, ordering Lamego and True Wearables to take all steps necessary to prevent the publication of confidential information in numerous patent applications. The Federal Circuit affirmed in January 2022. The trial court conducted a bench trial in March 2022, where Mr. Claassen and the team secured a ruling that Lamego misappropriated trade secrets, breached his fiduciary duty, and violated his employment agreements. The Court ordered Lamego to abandon patent applications containing Masimo trade secrets and return Masimo’s information. The Court enjoined the sale of True Wearables’ products that contained Masimo’s trade secret technology.
Apple, Inc. v. Masimo Corp, IPR2022-01271, IPR2022-01272. IPR2022-01273. IPR2022-01274, IPR2022-01275 (USPTO)
Mr. Claassen led the defense against six Apple petitions for inter partes review of Masimo pulse oximetry patents that formed the basis for an exclusion order from the International Trade Commission banning the import of certain Apple watches. The Patent Office denied all six petitions, agreeing with Masimo about the deficiencies in Apple’s hindsight analysis.
In re Certain Light-Based Physiological Measurement Devices and Components Thereof, 337-TA-1276 (U.S. International Trade Commission)
Mr. Claassen represented Masimo in a patent infringement investigation against Apple at the ITC that resulted in an import ban of certain Apple Watches. Mr. Claassen examined both parties’ expert witnesses and proved infringement of the asserted patents that led to the import ban.
Those Apple Watches, introduced after the pandemic started, included a “Blood Oxygen” feature to give a reading purporting to correspond to a user’s oxygen saturation. The parties tried the case in June 2022. In January 2023, an ITC Administrative Law Judge (ALJ) found that the Apple Watch infringes Masimo patents on technology for measuring oxygen in the blood and recommended exclusion of these watches. In October 2023, the ITC released its final determination and issued a limited exclusion order and cease and desist order against the Apple Watches at issue. In January 2024, the ban went into effect and Mr. Claassen represents Masimo in Apple’s appeal of the ban to the Federal Circuit.
Apple v. Masimo, C.A. Nos. 22-cv-1377-JLH and 22-cv-1378-JLH (D. Del)
Mr. Claassen is an essential member of the team defending Masimo and Sound United and counterclaimants Masimo and Cercacor Laboratories against Apple. As a result of Masimo’s pending trade secrets case against Apple (above) as well as Masimo’s success in securing an import ban on certain Apple Watch models, Masimo faces retaliatory litigation alleging that the company copied the Apple Watch. Mr. Claassen plays a major role in bringing counterclaims alleging antitrust violations, patent infringement, and false advertising claims against Apple. The case is significant in the matrix of ongoing litigation between Masimo and Apple.
Dominion Assets LLC v. Masimo Corp. and Cercacor Laboratories, Inc. (NDCA).
Represented defendants against three patents regarding non-invasive blood analyte monitoring. Obtained dismissal of a first suit for lack of standing at the time the complaint was filed. In a second case, Plaintiff dropped one patent after production of our expert report regarding the lack of infringement. Obtained summary judgment of invalidity, an order excluding plaintiff’s damages expert, and a covenant not to sue on all of plaintiff’s patents.
NueroGrafix et al. v. Toshiba Am. Medical Sys. (and related cases) (MDL).
Successfully defended Toshiba Medical against patent infringement claims regarding MRI.
American Vehicular Sciences LLC v. Toyota Motor Corporation (and related cases) (CACD and MIED).
Represented airbag manufacturer in significant non-practicing entity case asserting side-curtain airbag patent against defendants in automotive industry. Successfully transferred case, filed petitions for IPR, obtained a stay, and established unpatentability of asserted patents.
Digital Stream IP, LLC v. iHeartMedia, Inc. and Digital Stream IP, LLC v. CBS Radio, Inc. (TXED).
Represented iHeartMedia and CBS Radio in two infringement suits involving a patent allegedly related to HD radio technology bought by non-practicing entity, Digital Stream. The matter was resolved and dismissed.
Kreative Power, LLC v. Monoprice (NDCA).
Defended online retailer against claims of infringing utility patents, design patents, and copyrights relating to a power outlet/surge protector. Won summary judgment of invalidity and noninfringement within six months after the complaint was filed, with no need for depositions or a claim construction hearing.
Jimmy Styks LLC v. Hobie Cat Co., LLC (CACD).
Negotiated favorable settlement in patent infringement suit related to handles for stand up paddleboards resulting in dismissal of case with prejudice.
U.S. Ethernet Innovations Inc. v. Acer et al. (TXED and NDCA and CAFC).
Defended Toshiba Corporation to successfully obtain summary judgment in a significant non-practicing entity case. The plaintiff had sued over 30 defendants for infringing patents directed to Ethernet technology. Judge Claudia Wilken of the Northern District of California granted judgment of invalidity on two patents and non-infringement of two others. Successfully transferred the case from the Eastern District of Texas to the Northern District of California. Affirmed on appeal.
In the Matter of Certain Computer Notebook Products and Components Thereof, Inv. No. 337-TA-705 (USITC).
Obtained summary determination for complainant Toshiba regarding respondents’ affirmative defenses in patent infringement lawsuit involving hardware and software components of notebook computers.
Takata Corporation v. American Vehicular Sciences, LLC (IPR2016-1794).
Chief strategist for IPR petitioner that resulted in a final written decision finding all 44 claims of the challenged side-curtain airbag patent unpatentable on 13 grounds. Successfully established the lack of written description support for the challenged in the priority patent applications.
Toyoda Gosei Co. Ltd. v. American Vehicular Sciences, LLC (IPR2016-1790).
Obtained a final written decision finding all claims of the challenged airbag patent unpatentable. Demonstrated obviousness, including establishing reasons to combine and modification of prior art. Overcame evidence and arguments relating to objective considerations of non-obviousness.
Wilson Electronics, LLC v. CellPhone-Mate, Inc. d/b/a SureCall (IPR2018-1771, -1772, 1774, -1776, -1778, 01779).
Successfully represented SureCall’s 5-band cellphone booster patent against competitor challenge. Obtained non-institution of six petitons confirming patentability of all claims.
GameChanger Charity v. PlayNext, Inc. (CACD).
Successfully enforced trademark on behalf of owner.
Agri-Cover Inc. v. Ben Sabio (CACD).
Successfully enforced trademark on behalf of owner.
Kreative Power, LLC v. Monoprice (NDCA).
Defended online retailer against copyright claims relating to a power outlet/surge protector. Obtained summary judgment of invalidity and noninfringement within six months after the complaint was filed, with no need for depositions or a claim construction hearing.
Recognition
Awards & Honors
- Recognized as a “World IP Leader” by World Intellectual Property Review (WIPR) (2025)
- Recognized in Patexia’s 2023 PTAB Intelligence Report as a “Top Performer” based on activity and performance before the PTAB
- Named a “Southern California Rising Star” by Super Lawyers magazine for his work in intellectual property litigation (2014-2018)
- Howard T. Markey Inn of Court Program of the Year
- 2017 – 2018 “Inventorship Mystery Dinner Theater”
- 2015 – 2016 “IP Ethics”
Affiliations
Federal Bar Association – Orange County Chapter
President (Present-Nov 2022)
President Elect (2020-2021)
Treasurer (2019-2020)
Secretary (2018-2019)
Board Member (2016-2018)
Howard T. Markey Inn of Court
Membership Chair (2018-2019)
Program Chair (2017-2018)
ProVisors
News & Insights
Articles
Co-author, “Tips for Patent Prosecutors from Litigators: Enhancing Litigation Outcomes,” IP Watchdog, August 2024.
“Surfing and Skiing Make Me a Better Lawyer,” Law360 (June 2024).
Co-author, “FBA/OC Honors Don Martens with the Judge Alicemarie H. Stotler Award at Annual Judges’ Night” which was published in FBA/OC The Newsletter of the Federal Bar Association/Orange County Chapter. (May 2018).
Co-author, “Another Reason to Coordinate Discovery in Parallel Litigation – Circumvention in Section 1782 Requests,” International Litigation News, Newsletter of the International Bar Association Legal Practice Division (April 2013)
Speeches & Seminars
Brian Claassen and Joshua Harrison, Ph.D, “IPRs and the Courts,” OCBA Intellectual Property & Technology Law Section Meeting (March 29, 2019)
Howard T. Markey Inn of Court, “Expert Witnesses in Patent Litigation: From Teva to Trial” Irvine (March 2015)
Brian Claassen, “Intellectual Property Basics – SBIR/STTR and Tech Transfer,” Cal State Fullerton’s Research Week (March 22, 2013)