Santa Monica patent litigation boutique is the smallest firm ranked, one of only three firms newly ranked, and the only ranked firm principally focused on patent owner-side post-grant proceedings and related appeals
Santa Monica, California —Lowenstein & Weatherwax LLP has been ranked by Chambers USA 2026 in Intellectual Property: Patent Litigation — California, joining one of the most competitive patent litigation rankings in the country.
The recognition marks a major milestone for Lowenstein & Weatherwax. Chambers ranked only 37 firms in California for Intellectual Property: Patent Litigation, a group dominated by many of the country’s largest and best-known national and international law firms. Lowenstein & Weatherwax is the smallest firm ranked and one of only three firms newly ranked in the category this year.
Lowenstein & Weatherwax is also distinctive among the ranked firms for its focused practice model. Lowenstein & Weatherwax is the only ranked California patent litigation firm principally focused on representing patent owners in post-grant proceedings and related appeals.
“This recognition is meaningful because Chambers placed our boutique alongside the leading patent litigation departments in California,” said Nathan Lowenstein, founding partner of Lowenstein & Weatherwax. “We have always believed that a focused team with deep technical command, disciplined strategy, and excellent written and oral advocacy can compete with anyone. Chambers’ recognition reflects what our clients have known for years.”
Chambers described Lowenstein & Weatherwax as “a highly regarded litigation boutique” recognized for its “expert handling of inter partes reviews.” Chambers also noted that the firm represents a wide array of technology-sector clients and identified co-founders Nathan Lowenstein and Kenneth Weatherwax as key contacts.
Client feedback published by Chambers emphasized the firm’s PTAB experience, technical depth, strategy, and efficiency:
“L&W are very accomplished litigators, particularly when handling IPRs. They are able to navigate highly technical areas while also excelling in the legal and advocacy portions of an IPR.”
“The lawyers at Lowenstein & Weatherwax exhibit deep technical understanding for the patents involved in their matters. They are highly strategic when it comes to the policies and procedures of the USPTO, particularly as they relate to high-value patents.”
“Lowenstein & Weatherwax are able to handle work in any technology sector. They work efficiently and have meticulous strategy and written work product.”
The Chambers ranking follows years of independent recognition for the firm’s patent owner-side PTAB work. Lowenstein & Weatherwax has handled more than 400 IPR and CBM proceedings and nearly 80 Federal Circuit appeals. Patexia ranked Nathan Lowenstein #1 in Patent Owner Performance among 5,650 PTAB practitioners nationwide for the July 2020–June 2025 period. Patexia has also recognized Lowenstein & Weatherwax as the top-performing IPR firm for 2013–2018 and as the sixth most active and sixth best-performing firm representing patent owners for 2020–2025.
Lowenstein & Weatherwax represents patent owners in technically demanding disputes involving semiconductors, computer hardware and software, telecommunications, medical devices, biotechnology, digital video, electronic commerce, and other complex technologies. The firm’s practice includes patent owner-side IPR defense, patent reexaminations, post-grant strategy, institution-stage advocacy, Federal Circuit appeals, and related district court litigation.
“This is not a volume-practice recognition,” Lowenstein added. “Our work is highly focused. We are brought in for disputes where the technology is difficult, the stakes are high, and the written record matters. To be recognized by Chambers in a California table dominated by much larger firms is an important validation of that model.”
About Lowenstein & Weatherwax LLP
Lowenstein & Weatherwax LLP is a nationally recognized patent litigation boutique based in Santa Monica, California. The firm represents patent owners in high-stakes PTAB proceedings, patent reexaminations, Federal Circuit appeals, and related district court patent litigation. Lowenstein & Weatherwax is known for patent owner-side IPR defense, expert-driven technical analysis, institution-stage strategy, written and oral advocacy, and appellate work in complex patent validity disputes.