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 Wilson Sonsini Goodrich and Rosati, Gilead Sciences, and Debevoise & Plimpton LLP.

Top cities in California

All practitioners in California

Joel B Silver

Reg. 53866

Patent attorney

Gilead Sciences

Foster City, CA · 94404

650-425-8919

Daniel A. Silverman

Reg. 75922

Patent attorney

Debevoise & Plimpton LLP

San Francisco, CA · 94108

415-738-5700

Eric E. Silverman

Reg. 66832

Patent agent

Genentech Inc

South San Francisco, CA · 94080

650-225-1171

Lisa N Silverman

Reg. 69080

Patent attorney

Morrison & Foerster LLP

Palo Alto, CA · 94304

650-813-5735

Gary H Silverstein

Reg. 39372

Patent attorney

Carlsbad, CA · 92009

760-672-6221

Sheryl R Silverstein

Reg. 40812

Patent attorney

Ionis Pharmaceuticals

Carlsbad, CA · 92010

760-603-3887

James N. Silverthorn

Reg. 81390

Patent agent

Sacramento, CA · 95864

858-254-7570

Vanessa K. Sim

Reg. 79895

Patent attorney

Kirkland & Ellis

Los Angeles, CA · 90036

213-680-8400

Paul B Simboli

Reg. 38616

Patent attorney

Depomed, Inc.

Newark, CA · 94560

510-744-8000

Jayanthi G Simha

Reg. 66623

Patent agent

Saratoga, CA · 95070

408-446-4138

Craig A Simmermon

Reg. 58133

Patent attorney

Craig A. Simmermon, Attorney at Law

Sacramento, CA · 95814

916-878-6656

Laura C Simmons

Reg. 50727

Patent attorney

Burlingame, CA · 94011

Atussa K Simon

Reg. 72731

Patent attorney

Wilson Sonsini Goodrich and Rosati

Palo Alto, CA · 94304

650-496-4041

Brenda M Simon

Reg. 48449

Patent attorney

San Diego, CA · 92130

510-393-3484

David Mark Simon

Reg. 32756

Patent attorney

David M Simon

Los Gatos, CA · 95032

408-402-3476

James Lowell Simon

Reg. 31139

Patent attorney

James L. Simon

San Jose, CA · 95124

408-859-4397

Ryan M Simon

Reg. 61949

Patent attorney

San Diego, CA · 92129

619-252-9197

Anna R. F. Simonin

Reg. 84311

Patent agent

Wilson Sonsini Goodrich & Rosati

San Francisco, CA · 94105

415-744-4282

Pamela Angela Simonton

Reg. 31060

Patent attorney

Burlingame, CA · 94010

650-344-9441

Amy E Simpson

Reg. 54688

Patent attorney

Perkins Coie, LLP

San Diego, CA · 92130-3334

858-720-5702

Andrew Harding Simpson

Reg. 31469

Patent attorney

Knobbe Martens Olson and Bear

Irvine, CA · 92614

949-760-0404

Palmer Martin Simpson· Jr

Reg. 28118

Patent attorney

San Francisco, CA · 94109

415-447-5422

David L. Simson

Reg. 76052

Patent attorney

Goodwin Procter LLP

Redwood City, CA · 94063

650-752-3124

Kevin Sin

Reg. 47091

Patent attorney

Wilson Sonsini Goodrich and Rosati

Palo Alto, CA · 94304

650-493-9300

Ajay Singh

Reg. 63351

Patent attorney

San Rafael, CA · 94903

720-352-2706

Davinder Singh

Reg. 55621

Patent agent

Intel Corp.

Milpitas, CA · 95035

408-839-1616

Gurneet Singh

Reg. 70234

Patent attorney

Jones Day

Palo Alto, CA · 94303

650-687-4108

Gurtej Singh

Reg. 71020

Patent attorney

Hogan Lovells Cadwalader

Redwood City, CA · 94063

650-463-4000

Harpreet Singh

Reg. 71842

Patent attorney

DLA Piper, LLC

East Palo Alto, CA · 94303

650-833-2000

Himanshu Singh

Reg. 67901

Patent attorney

Xero

San Francisco, CA · 94111

415-815-9830

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.