ATTORNEYS
Doug Muehlhauser
University of San Diego | JD
Pepperdine University | MBA
UCSD | BA Computer Science
Doug has been litigating high-tech patent cases nation-wide for over 30 years. As lead counsel, he has achieved victories for his clients at trial, on appeal, at the U.S. International Trade Commission (ITC), in early dismissals, and in numerous license deals and settlements. As lead trial counsel for a high-tech computer networking company, Doug strategically litigated a substantial portfolio of network router patents for over 16 years, generating over $100 million in revenue. Doug also has a remarkable record in Inter Partes Review (IPR) proceedings, successfully defending patent owners on over 50 petitions. While Doug's cases extend into many scientific fields, including pharmaceuticals, telecommunications and laboratory equipment, he brings particular expertise to his software-related cases in which he leverages his 10 years of software development experience prior to joining the legal profession. Doug has been recognized in 2026 in the 32nd Edition of Best Lawyers in America.
Doug is a registered patent attorney and member of the California state Bar.
Payson LeMeilleur
University of Virginia | JD
USC | BS Physics magna cum laude
Payson has been counseling clients on intellectual property matters, with an emphasis on patent litigation, for over 25 years. He has extensive experience in jury and bench trials in United States District Courts across the country, as well as in trials before the ITC and the PTO in IPR proceedings. Payson also has significant appellate experience, including before the United States Court of Appeals for the Federal Circuit and the Ninth Circuit. He has successfully litigated complex patent matters against the largest corporations and is adept in handling cases involving highly technical subject matter such as electronic devices, wireless protocols, computer networking and pharmaceuticals. Prior to founding MacArthur James, Payson was a partner at a national intellectual property law firm of over 250 lawyers, where he chaired both the firm's Recruiting Committee and Mentor Committee.
Payson is a member of the California and Texas state Bars.
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