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 Knobbe, Martens, Olson & Bear, LLP, Technology Transfer Office, and Martine Penilla Group LLP.

Top cities in California

All practitioners in California

Sarah K. Martin

Reg. 80439

Patent agent

Esconido, CA · 92025

760-520-5336

Jose A. Martin del Campo

Reg. 79610

Patent agent

Knobbe, Martens, Olson & Bear, LLP

Irvine, CA · 92614

949-721-5340

Edward T Martindale

Reg. 69725

Patent attorney

Technology Transfer Office

San Diego, CA · 92182-8220

619-594-0791

Peter B Martine

Reg. 32043

Patent attorney

Martine Penilla Group LLP

Sunnyvale, CA · 94085

408-749-6900

Jason R. Martineau

Reg. 61398

Patent attorney

Samsung Semiconductor Inc.

San Jose, CA · 95134

408-544-4283

Joshua Michael Martineau

Reg. 79242

Patent attorney

Knobbe, Martens, Olson & Bear, LLP

Irvine, CA · 92614

212-849-3000

Alexander J Martinez

Reg. 75319

Patent attorney

Knobbe, Martens, Olson & Bear, LLP

Irvine, CA · 92614

949-760-0404

Cassidy L. Martinez

Reg. 76321

Patent attorney

Rohnert Park, CA · 94928

707-236-0784

Joanne T. Martinez

Reg. 60096

Patent attorney

San Francisco, CA · 94117

850-727-1392

Jose F. Martinez

Reg. 78122

Patent agent

Wilson Sonsini Goodrich and Rosati

Palo Alto, CA · 94304-1050

541-400-0071

Michelle N Martinez

Reg. 68549

Patent attorney

Irvine, CA · 92618

801-455-4837

Peter Raphael Martinez

Reg. 42845

Patent attorney

Law Office of Peter Martinez, Esq.

Woodland Hills, CA · 91367

858-449-0612

Raul D Martinez

Reg. 46904

Patent attorney

GPC Properties, LLC

Santa Monica, CA · 90404

310-592-2015

Sheila P Martinez-Lemke

Reg. 52004

Patent attorney

Kwan & Olynick L LP

Berkeley, CA · 94704

510-900-9501

Nicholas V. Martini

Reg. 69094

Patent attorney

Adobe Systems, Inc.

San Jose, CA · 95113

408-536-6692

Marc G. Martino

Reg. 65695

Patent agent

Westlake Village, CA · 91362

818-825-0988

Ani Martirosian

Reg. 79109

Patent attorney

Glendale, CA · 91202

818-749-1243

Jason C Martone

Reg. 59469

Patent attorney

Lewis Roca Rothgerber Christie LLP

Irvine, CA · 92612

949-476-0757

Eric S Marzluf

Reg. 27454

Patent attorney

La Quinta, CA · 92253

215-327-2245

Keiji Masaki

Reg. 45322

Patent agent

INTERNATIONAL KNOWLEDGE ASSET OFFICE

Irvine, CA · 92612

949-954-0811

Eric G Masamori

Reg. 46360

Patent attorney

Law Office of Eric G. Masamori

Walnut Creek, CA · 94598

925-947-1002

Mary A Mashruwala

Reg. 61707

Patent agent

Prolacta Bioscience

Duarte, CA · 91010

832-496-5979

John C Masiewicz

Reg. 60597

Patent agent

Western Digital

San Jose, CA · 95138-1857

949-363-4259

Victoria K Maskiewicz

Reg. 42750

Patent agent

Loma Linda University

Loma Linda, CA · 92350

909-558-9754

David M Mason

Reg. 42846

Patent agent

Align Technology, Inc.

San Jose, CA · 95131

408-470-1000

Diane J Mason

Reg. 43777

Patent attorney

Bullivant Houser Bailey PC

San Francisco, CA · 94108-2823

415-352-2758

Terrance Mason

Reg. 53280

Patent agent

Studio City, CA · 91604

818-808-3147

Kenneth M Massaroni

Reg. 33015

Patent attorney

Seagate Technology Plc

Cupertino, CA · 95014

952-402-8447

Cory A. Massey

Reg. 80349

Patent agent

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

San Diego, CA · 92130

858-314-1578

Ofer I Matalon

Reg. 39439

Patent attorney

Santa Rosa, CA · 95405

310-403-1233

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.