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 The Clorox Company, Yingli Green Energy Americans, Inc., and DLA Piper, LLP(US).

Top cities in California

All practitioners in California

Stacy Hegle Combs

Reg. 50687

Patent agent

The Clorox Company

Oakland, CA · 94612

925-425-6905

Joseph A Compton

Reg. 34308

Patent agent

Encino, CA · 91436

818-388-1201

Leonard D. Conapinski

Reg. 66048

Patent attorney

Yingli Green Energy Americans, Inc.

San Francisco, CA · 94108

415-728-0468

Michael P Condakes

Reg. 80961

Patent attorney

Palo Alto, CA · 94302

408-499-0509

Celine I Conde

Reg. 79388

Patent agent

DLA Piper, LLP(US)

San Diego, CA · 92121

858-677-1422

Debra Dahl Condino

Reg. 31007

Patent attorney

Allergan, Inc.

Irvine, CA · 92612

714-246-2388

Deirdre L Conley

Reg. 36487

Patent attorney

South San Francisco, CA · 94080

650-588-7576

James P Conley

Reg. 52459

Patent attorney

Pillsbury Winthrop Shaw Pittman LLP

San Diego, CA · 92130-4088

858-509-4050

Robert T Conley

Reg. 50952

Patent attorney

Pasadena, CA · 91104

Brenda J Conner

Reg. 55082

Patent agent

Orrick, Herrington & Sutcliffe, LLP

Irvine, CA · 92614-8255

949-567-6700

Margaret Ann Connor

Reg. 30043

Patent attorney

El Cerrito, CA · 94530

510-528-1952

Michael J Connor· Jr.

Reg. 64284

Patent agent

San Diego, CA · 92109

248-535-5829

John Joseph Connors

Reg. 24157

Patent attorney

Connors & Associates pc

Seal Beach, CA · 90740

949-833-3622

Lara Connors

Reg. 42432

Patent agent

Pleasanton, CA · 94566

925-462-1224

Paul N Conover

Reg. 44087

Patent attorney

Knobbe Marten Olson and Bear, LLP

Irvine, CA · 92614

949-760-0404

Eugene C Conser

Reg. 39149

Patent agent

Conser & Assoc.

San Jose, CA · 95120

408-268-5161

Sabrina E Contreras

Reg. 84603

Patent agent

Martinez, CA · 94553

918-804-1210

Brian M. Cook

Reg. 59356

Patent agent

Altadena, CA · 91001

626-794-9284

Carmen C Cook

Reg. 42433

Patent attorney

San Jose, CA · 95131

408-658-8094

Christopher P Cook

Reg. 71443

Patent attorney

Zilka Kotab, P.C.

Santa Clara, CA · 95051

408-971-2573

Roger Lee Cook

Reg. 24648

Patent attorney

KILPATRICK TOWNSEND & STOCKTON, LLP

San Francisco, CA · 94111

415-576-0200

Sangeeta B Cook

Reg. 72582

Patent agent

Beckman Research Institute of the City of Hope

Duarte, CA · 91010

626-471-3791

Thomas W Cook

Reg. 38849

Patent attorney

Sausalito, CA · 94965

415-339-8550

Darren D Cooke

Reg. 55084

Patent attorney

Law Office of Darren D. Cooke

Orinda, CA · 94563

415-205-5037

Warren P. Coon

Reg. 59504

Patent agent

San Diego, CA · 92150

858-449-3984

Thomas F Cooney

Reg. 54046

Patent agent

Thermo Fisher Scientific

San Jose, CA · 95134

408-965-6345

Eric A Cooper

Reg. 61613

Patent agent

Los Altos, CA · 94022

650-947-9654

Geoffrey K. Cooper

Reg. 51266

Patent agent

Fort Jones, CA · 96032-9507

530-468-2289

John W Cooper

Reg. 80558

Patent attorney

Glendale, CA · 91222

626-944-3800

Stephen Randolph Cooper

Reg. 42437

Patent agent

Carlsbad, CA · 92008

760-696-7509

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.