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 Nicholson De Vos Webster & Elliott LLP, Perkins Coie, LLP, and Farella, Braun Martel, LLP.

Top cities in California

All practitioners in California

Evan S Day

Reg. 75992

Patent attorney

Perkins Coie, LLP

San Diego, CA · 92130

858-720-5700

James L. Day· Jr.

Reg. 72681

Patent attorney

Farella, Braun Martel, LLP

San Francisco, CA · 94104

415-954-4400

Michael L Day

Reg. 55101

Patent attorney

Weaver Austin Villeneuve & Sampson LLP

Oakland, CA · 94612-0250

510-663-1100

Michael L Day

Reg. 65069

Patent attorney

Los Angeles, CA · 90015

202-627-8288

Darick Dayne

Reg. 63056

Patent agent

Menlo Park, CA · 94025

Christopher A Dayton

Reg. 35114

Patent attorney

Del Mar, CA · 92014

858-337-0469

William J. Dayton

Reg. 84472

Patent agent

Torrance, CA · 90503

424-285-9496

Rhea C De Aenlle

Reg. 45994

Patent attorney

Pepper Hamilton LLP

Irvine, CA · 92614-5955

949-567-3500

Michael John B. de Blank

Reg. 74930

Patent attorney

Orrick Herrington & Sutcliffe, LLP

Menlo Park, CA · 94025

650-614-7400

Richard V De Gruccio

Reg. 50898

Patent attorney

Roseville, CA · 95661

916-567-1400

Patricia J de Guzman

Reg. 42469

Patent attorney

Google LLC

Mountain View, CA · 94043

650-695-8973

Victor S. de Gyarfas

Reg. 40583

Patent attorney

Foley & Lardner LLP

Los Angeles, CA · 90071

213-972-4500

Jason Don Ancheta de Jesus

Reg. 77432

Patent attorney

Los Angeles, CA · 90026

213-284-8835

Stephen M De Klerk

Reg. 46503

Patent attorney

Law Office of Stephen M. De Klerk

Los Altos, CA · 94024

650-823-3835

Manuel Federio de la Cerra

Reg. 45776

Patent attorney

The Law Office of Manuel de la Cerra

Carlsbad, CA · 92011

760-809-5520

Andre De La Cruz

Reg. 57229

Patent attorney

Irvine, CA · 92602

213-700-5703

Tanya R de la Fuente

Reg. 51600

Patent attorney

de la Fuente McHenry Law

Campbell, CA · 95008

408-377-3977

Virginia T. de la Puente

Reg. 45948

Patent attorney

Lawrence Berkeley National Laboratory

Berkeley, CA · 94720

510-495-2920

K Alison de Runtz

Reg. 37119

Patent attorney

Berkeley, CA · 94707

510-525-4234

Daniel M De Vos

Reg. 37813

Patent attorney

Nicholson De Vos Webster & Elliott LLP

San Jose, CA · 95113-1605

408-675-5565

Christopher G. De Vry

Reg. 61425

Patent attorney

BioMarin Pharmaceutical, Inc.

Novato, CA · 94949

415-842-8040

Joel Jason De Young

Reg. 26264

Patent attorney

San Francisco, CA · 94127

775-453-5300

Aldo DeAmicis

Reg. 62064

Patent agent

Fremont, CA · 94536

510-284-7442

Ryan S Dean

Reg. 61570

Patent attorney

Umberg Zipser LLP

Irvine, CA · 92614

949-679-0052

Maryanne E DeAngelo

Reg. 47228

Patent attorney

Innovation Nation IP Law

Cardiff by the sea, CA · 92007

760-809-6004

Marcel Frederick DeArmas

Reg. 64285

Patent attorney

Mitchell + Company

San Francisco, CA · 94111

415-944-9789

Bryce D Deary

Reg. 42470

Patent attorney

Culver City, CA · 90231

310-293-1463

Chaarushena Deb

Reg. 81857

Patent attorney

Latham & Watkins

Menlo Park, CA · 94025

650-470-2160

Meriem Debbih

Reg. 73922

Patent agent

Nicholson De Vos Webster & Elliott LLP

Palo Alto, CA · 94103

408-664-9266

Lisa G Deberg

Reg. 56524

Patent agent

10X Genomics

Pleasanton, CA · 94588

608-215-3532

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.