California

Patent attorneys in California

California hosts 9,553 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 Corbion Biotech, Inc.,, Xilinx, and Gilead Sciences, Inc..

Top cities in California

All practitioners in California

Jeong Y. Choi

Reg. 71625

Patent attorney

Palo Alto, CA · 94302

650-380-3227

Kathleen Limjoo Choi

Reg. 43433

Patent attorney

Corbion Biotech, Inc.,

South San Francisco, CA · 94080

415-840-8264

Luke B. Choi

Reg. 77709

Patent attorney

Xilinx

San Jose, CA · 95124

408-879-7179

Lydia B Choi

Reg. 73733

Patent attorney

Gilead Sciences, Inc.

Foster City, CA · 94404

650-653-9461

Moses S Choi

Reg. 76649

Patent agent

Brea, CA · 92821

714-824-9988

Sandy Choi

Reg. 64933

Patent attorney

San Francisco, CA · 94118

415-730-4271

Yongjin Choi

Reg. 61915

Patent attorney

Xencor, Inc.

Pasadena, CA · 91107

626-737-8156

Yue Yin Choi

Reg. 69767

Patent agent

Sunnyvale, CA · 94085

408-872-5339

Stephanie N. Choing

Reg. 76542

Patent agent

Morrison and Foerster LLP

San Francisco, CA · 94105-2482

415-268-6431

Eugene K Chong

Reg. 69409

Patent attorney

Chong IP Law Group

Pasadena, CA · 91101

213-298-3085

Nathaniel P. Chongsiriwatana

Reg. 65676

Patent attorney

Neurocrine Biosciences, Inc.

San Diego, CA · 92130

858-723-2904

Barry Choobin

Reg. 60128

Patent agent

Patent 360 LLC

Irvine, CA · 92612

949-418-7674

Gregory A Chopskie

Reg. 43547

Patent attorney

Pierson Ferdinand LLP

Palo Alto, CA · 94303

202-258-4998

Alain J. Chorbajian

Reg. 78300

Patent attorney

Law Offices of Vatche Chorbajian, APC

Rancho Santa Fe, CA · 92067

858-759-8822

Ilya Chorny

Reg. 56519

Patent agent

San Diego, CA · 92103

408-887-8496

Catherine S Chou

Reg. 75815

Patent attorney

Morgan, Lewis & Bockius LLP

Palo Alto, CA · 94304

650-843-4000

Chien W Chou

Reg. 41672

Patent attorney

K&L Gates LLP

San Francisco, CA · 94111

415-882-8200

Danny Y Chou

Reg. 41673

Patent attorney

Santa Clara County Counsel's Office

San Jose, CA · 95110

408-299-5900

Evelyn S. Chou

Reg. 79300

Patent agent

Morgan Lewis & Bokius LLP

San Francisco, CA · 94105

415-442-1609

Grace F Chou

Reg. 45637

Patent agent

Danisco US Inc.

Palo Alto, CA · 94304

650-846-7535

Jonathan K. Chou

Reg. 70427

Patent attorney

Weaver Austin Villeneuve & Sampson LLP

Oakland, CA · 94607

Wei Chi Chou

Reg. 76948

Patent attorney

Trojan Law Offices

Beverly Hills, CA · 90212

213-716-5063

Andrew Y Choung

Reg. 46622

Patent attorney

Nixon Peabody LLP

Los Angeles, CA · 90071

213-629-6166

Christopher S Chow

Reg. 46493

Patent attorney

Qualcomm

San Diego, CA · 92121-1714

858-845-3249

Elaine Y Chow

Reg. 46191

Patent attorney

San Francisco, CA · 94116

415-483-5795

Harold J Chow

Reg. 55068

Patent attorney

Los Altos, CA · 94022

650-903-9888

Judy L. Chow

Reg. 79885

Patent agent

Santa Ana, CA · 92704

562-818-1130

Y Ping Chow

Reg. 30740

Patent agent

SiPix Imaging, Inc.

Fremont, CA · 94538

510-743-2804

Bharat M Chowrira

Reg. 47491

Patent attorney

Nektar Therapeutics

San Carlos, CA · 94070

650-631-3100

Calvin Choy

Reg. 80526

Patent agent

Los Angeles, CA · 90071

424-305-8306

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?

9,553 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.