California

Patent attorneys in California

California hosts 9,567 active patent practitioners registered with the USPTO Office of Enrollment and Discipline. Patent attorneys and patent agents can both prepare and file patent applications, but only patent attorneys can also offer legal advice on prosecution strategy, freedom-to-operate analyses, and infringement opinions in California. Practitioners are concentrated across 20 cities, with the largest clusters in the metros listed below. Notable firms with multiple registered practitioners in the state include Trend Micro Inc., ASML, and Xerox Corp. (Office of General Counsel).

Top cities in California

All practitioners in California

John C Chen

Reg. 39136

Patent attorney

Trend Micro Inc.

Cupertino, CA · 95014

408-863-6465

Julie P. Chen

Reg. 66309

Patent agent

Mountain View, CA · 94040

650-695-3468

Jun Chen

Reg. 70340

Patent agent

ASML

San Jose, CA · 95131

312-404-2708

Kent Mark Chen

Reg. 39630

Patent attorney

Xerox Corp. (Office of General Counsel)

Santa Ana, CA · 92705

714-565-1158

Kevin J. Chen

Reg. 80258

Patent agent

San Jose, CA · 95129

408-207-3345

L. Howard Chen

Reg. 46615

Patent attorney

K & L Gates

San Francisco, CA · 94105

415-882-8200

Lili Chen

Reg. 60780

Patent agent

LotusWP Agency

San Diego, CA · 92130

858-208-3828

Lily Li-Ling Chen

Reg. 44605

Patent attorney

Millbrae, CA · 94030

Linna R Chen

Reg. 52726

Patent attorney

Linna Chen Intellectual Property Law Group

Santa Clara, CA · 95054

141-529-92149

Matthew H Chen

Reg. 83988

Patent agent

San Diego, CA · 92126

609-235-5034

Matthew S Chen

Reg. 61558

Patent attorney

Menlo Park, CA · 94025

650-455-5264

Michael Ying-Hsuan Chen

Reg. 66506

Patent agent

Haynes and Boone, LLP

Costa Mesa, CA · 92626

949-202-3069

Michael S Chen

Reg. 62142

Patent agent

Jackson & Co., LLP

Oakland, CA · 94611

510-652-6418

Peisong Chen

Reg. 61994

Patent agent

Broadcom Corpartion

San Diego, CA · 92127

858-521-4835

Peng Chen

Reg. 43543

Patent attorney

Rimon PC

San Diego, CA · 92121

619-607-3645

Peter P Chen

Reg. 39631

Patent attorney

Covington & Burling LLP

Palo Alto, CA · 94306

650-632-4700

Philip T Chen

Reg. 52727

Patent attorney

Kirkland and Ellis

Los Angeles, CA · 90017

213-680-8341

Po-An Chen

Reg. 84178

Patent agent

Knobbe Martens Olson & Bear, LLP

Irvine, CA · 92614

949-721-2835

Qing Chen

Reg. 79899

Patent agent

Los Gatos, CA · 95032

408-410-2870

Quynh M. Chen

Reg. 76786

Patent attorney

Polsinelli LLP

San Francisco, CA · 94111

415-248-2133

Shengfeng Chen

Reg. 57430

Patent attorney

Intellectual Valley Law, P.C.

Fremont, CA · 94538

510-666-6400

Shijia Chen

Reg. 63449

Patent agent

Diamond Bar, CA · 91765

626-290-3007

Shiyan Chen

Reg. 81624

Patent agent

Claremont, CA · 91711

909-247-4112

Si Chen

Reg. 80259

Patent attorney

Lam Research Corporation

Fremont, CA · 94538

510-572-6663

Spencer S Chen

Reg. 42405

Patent attorney

Menlo Park, CA · 94025-4608

650-353-7881

Stacy S Chen

Reg. 62609

Patent agent

Irvine, CA · 92620

949-378-9729

Stephen W. Chen

Reg. 60629

Patent agent

Nixon Peabody LLP

Los Angeles, CA · 90071-3151

213-629-6000

Steven P Chen

Reg. 64373

Patent attorney

Broadview IP Law, PC

Irvine, CA · 92602

949-232-0721

Taian Chen

Reg. 75437

Patent agent

Saratoga, CA · 95070

650-302-8499

Theodore A Chen

Reg. 40557

Patent attorney

Calix Inc.

San Jose, CA · 95117

408-514-3000

Common questions

Do I need a patent attorney based in California?

No. Every USPTO-registered patent practitioner is licensed to file applications on behalf of inventors in any state, regardless of where the practitioner's office is. Choosing a California-based practitioner can simplify in-person inventor signings, local meetings, and same-time-zone calls, but it is not a legal requirement.

How many patent attorneys are licensed in California?

9,567 active USPTO-registered patent practitioners list a California office address on the OEDCI roster. This includes both patent attorneys (who can also offer legal advice) and patent agents (who can prepare and file patents but not offer broader legal advice).

What is the difference between a patent attorney and a patent agent?

Both pass the USPTO Patent Bar and can prepare, file, and prosecute patent applications. Only patent attorneys also hold a state bar license, meaning they can additionally offer legal advice on infringement, licensing, and litigation strategy. Patent agents tend to charge less per hour and are common at large in-house IP departments.