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 Law Office of Michael Williamson, Willink & Hunt LLp, and Informatica Corporation.

Top cities in California

All practitioners in California

Tim A Williams

Reg. 50790

Patent agent

Danville, CA · 94506

925-984-5148

Michael V Williamson· Jr

Reg. 66040

Patent attorney

Law Office of Michael Williamson

Clayton, CA · 94517

925-408-4470

Christopher L. Willink

Reg. 62135

Patent attorney

Willink & Hunt LLp

San Francisco, CA · 94117

415-993-5400

Kathy S Willis

Reg. 36722

Patent attorney

Informatica Corporation

Redwood City, CA · 94063

650-385-6077

Michael A Willis

Reg. 53913

Patent attorney

EdenRoc Sciences, LLC

Sunnyvale, CA · 94085

510-990-5699

George A Willman

Reg. 41378

Patent attorney

Pillsbury Winthrop Shaw Pittman LLP

Palo Alto, CA · 94304-1115

650-233-4500

Belinda S Willoughby

Reg. 66749

Patent agent

San Francisco, CA · 94122

650-293-7652

Alexandra M Wilson

Reg. 56710

Patent agent

Irvine, CA · 92603

949-735-3938

Barry S Wilson

Reg. 39431

Patent attorney

San Diego, CA · 92120

619-701-0331

Brad A Wilson

Reg. 59462

Patent attorney

Maschoff Brennan

Irvine, CA · 92618

949-202-1791

Brock F Wilson

Reg. 59463

Patent attorney

McDermott Will & Emery LLP

Irvine, CA · 92612-7108

949-851-0633

Christopher G. Wilson

Reg. 66127

Patent attorney

Sidley Austin LLP

Los Angeles, CA · 90013

213-896-6174

Crystal Dee Wilson

Reg. 61730

Patent agent

Thermo Fisher Scientific

Carlsbad, CA · 92008

571-420-2973

Erica D Wilson

Reg. 42230

Patent attorney

Walters Wilson LLP

Redwood City, CA · 94063

650-248-4586

James C Wilson

Reg. 35412

Patent attorney

Applied Materials, Inc.

Santa Clara, CA · 95052

408-563-2733

Keith M Wilson

Reg. 40230

Patent attorney

IPVALUE Management, Inc.

Santa Clara, CA · 95054

480-869-4007

Mark A Wilson

Reg. 43275

Patent attorney

Septerna, Inc.

South San Francisco, CA · 94080

650-338-3533

Mark A Wilson

Reg. 43994

Patent attorney

Loza & Loza, LLP

Pleasanton, CA · 94566

925-249-1300

Minda S Wilson

Reg. 52369

Patent agent

Oak Park, CA · 91377

818-865-2818

Rachel H. Wilson

Reg. 81214

Patent agent

Palo Alto, CA · 94304

303-945-0573

Rachel L. Wilson

Reg. 82529

Patent agent

Wilson, Sonsini, Goodrich & Rosati

San Francisco, CA · 94105

415-947-2119

Richa Wilson

Reg. 54543

Patent agent

Ernest Gallo Clinic & Research Center

Emeryville, CA · 94608

510-985-3112

Steven A. Wilson

Reg. 65345

Patent attorney

Hawthorne, CA · 90250

310-920-3739

Tyson York Winarski

Reg. 41381

Patent attorney

Mountain View, CA · 94040

480-244-8379

Laura L Wine

Reg. 68681

Patent attorney

Allergan, Inc.

Irvine, CA · 92612

714-246-6996

Brett M. Wingeier

Reg. 69895

Patent agent

San Francisco, CA · 94131

415-690-7358

Monica H Winghart

Reg. 46790

Patent attorney

Article One Partners

Palo Alto, CA · 94301

510-303-0696

Aaron R Wininger

Reg. 45229

Patent attorney

Schwegman Lundberg & Woessner, P.A.

San Jose, CA · 95128

408-278-4059

Jeffrey William Winkelman

Reg. 43278

Patent attorney

Mirati Therapeutics, Inc.

San Diego, CA · 92121

858-332-3513

Blake A. Winn

Reg. 84796

Patent attorney

Irvine, CA · 92618

434-981-3136

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.