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 LOZA & LOZA, LLP, DeHay & Elliston, L.L.P., and Sidley Austin LLP.

Top cities in California

All practitioners in California

Gautam Thatte

Reg. 75568

Patent agent

San Diego, CA · 92128

213-999-2054

Siariya S Thavonekham

Reg. 58611

Patent attorney

LOZA & LOZA, LLP

Upland, CA · 91786

714-453-9824

Jeffrey T Thayer

Reg. 48530

Patent attorney

DeHay & Elliston, L.L.P.

Oakland, CA · 94607

510-285-0750

M Patricia Thayer

Reg. 32244

Patent attorney

Sidley Austin LLP

San Francisco, CA · 94104-2878

415-772-7469

Justin K Theam

Reg. 81888

Patent attorney

Greenberg Traurig, LLP

Los Angeles, CA · 90067

310-586-7700

Thomas D Theisen

Reg. 35713

Patent attorney

San Diego, CA · 92101

619-255-0000

Harry G Thibault

Reg. 26347

Patent attorney

IP Consulting

Hayward, CA · 94540

510-909-2488

Thomas M Thibault

Reg. 42181

Patent attorney

Thibault Patent Group

San Diego, CA · 92172

858-735-1097

Steven R Thiel

Reg. 53685

Patent attorney

QUALCOMM Incorporated

San Diego, CA · 92121

858-651-7298

Tara L. Thieme

Reg. 68789

Patent attorney

ON24, Inc.

San Francisco, CA · 94105

920-889-4077

Rose M Thiessen

Reg. 40202

Patent attorney

Epitracker, Inc.

San Diego, CA · 92126

619-342-5756

Richard W Thill

Reg. 53686

Patent attorney

The Law Office of Richard W. Thill

San Diego, CA · 92103

619-821-0394

Austin G. Thind

Reg. 82694

Patent attorney

Cooley LLP

San Diego, CA · 92121

858-550-6287

Megan N. Thobe

Reg. 75453

Patent attorney

Amgen Inc.

Thousand Oaks, CA · 91320

805-313-7318

Charles Louis Thoeming

Reg. 43951

Patent attorney

Law Offices of Charles L. Thoeming

Lafayette, CA · 94549

925-835-7190

Colin N Thom

Reg. 71951

Patent agent

Stanford, CA · 94305

650-387-6189

C Douglass Thomas

Reg. 32947

Patent agent

T. I. Law Group, PC

San Jose, CA · 95131

408-955-0535

Charles A. Thomas

Reg. 75494

Patent attorney

KPPB, LLC

Anaheim, CA · 92806

949-852-0000

Charles H Thomas· Jr

Reg. 25710

Patent attorney

Long Beach, CA · 90803

562-434-9416

Gerald B. Thomas

Reg. 64464

Patent agent

Polsinelli LLP

San Francisco, CA · 94111

415-248-2128

Julia Anne Thomas

Reg. 52283

Patent agent

Menlo Park, CA · 94025

650-868-9192

Justin P Thomas

Reg. 63301

Patent attorney

Shay Glenn LLP

San Mateo, CA · 94403

650-287-2165

Mark S. Thomas

Reg. 83197

Patent agent

SET Industries Corporation

Cupertino, CA · 95014

510-301-4562

Michael J Thomas

Reg. 40840

Patent attorney

Downey Brand, LLP

Sacramento, CA · 95814

916-444-1000

Tiffany B Thomas

Reg. 55589

Patent agent

Kilpatrick Townsend & Stockton LLP

San Diego, CA · 92130

858-350-6151

Andrew N Thomases

Reg. 40841

Patent attorney

Skadden, Arps, Slatew, Meagher & Flom LLP

Palo Alto, CA · 94301

650-470-4500

Alan H Thompson

Reg. 29981

Patent attorney

Law Office of Alan H. Thompson

Livermore, CA · 94551

925-337-6889

Davis R Thompson

Reg. 73659

Patent attorney

Pasadena, CA · 91106

626-639-6562

Jillian Basinger Thompson

Reg. 75687

Patent agent

Mintz Levin Cohn Ferris Glovsky and Popeo PC

San Diego, CA · 92130

858-314-1564

Lynn M Thompson

Reg. 47991

Patent agent

Spinal Modulation, Inc

Menlo Park, CA · 94025

650-543-6826

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.