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 Dhillon Law Group Inc., Sanjiv N. Singh, A Professional Law Corporation, and University of San Francisco School of Law.

Top cities in California

All practitioners in California

Jhujhaar Singh

Reg. 64801

Patent agent

San Leandro, CA · 94577

510-803-5035

Nitoj P Singh

Reg. 64735

Patent attorney

Dhillon Law Group Inc.

San Francisco, CA · 94108

510-520-9087

Sanjiv N Singh

Reg. 55622

Patent attorney

Sanjiv N. Singh, A Professional Law Corporation

San Francisco, CA · 94111

415-296-0152

Taylor Singh

Reg. 902320

Limited recognition

University of San Francisco School of Law

San Francisco, CA · 94117-1080

707-799-4695

Tejinder Singh

Reg. 39535

Patent attorney

Klein, O'Neill & Singh LLP

Irvine, CA · 92606

949-955-1920

Timothy J Singleton

Reg. 69759

Patent attorney

Schwegman Lundberg & Woessner

San Jose, CA · 95113

612-373-6900

Santosh C Sinha

Reg. 78336

Patent agent

Ladera Ranch, CA · 92694

949-365-6157

Xhavin Sinha

Reg. 73748

Patent attorney

Santa Clara, CA · 95054

408-791-0432

Robert K. Sink

Reg. 58260

Patent attorney

Fenwick & West LLP

Mountain View, CA · 94041

650-335-7301

Jonathan J. Sip

Reg. 64461

Patent attorney

San Francisco, CA · 94116

408-483-8914

Jayant S Sirdesai

Reg. 76662

Patent agent

Irvine, CA · 92614

949-394-8207

Charles J. Sirek

Reg. 79806

Patent attorney

Knobbe, Martens, Olson & Bear, LLP

Irvine, CA · 92614

949-760-0404

Smith Sirisakorn

Reg. 65056

Patent attorney

Hawthorne, CA · 90250

310-683-3491

Eugene Sisman

Reg. 69354

Patent agent

San Diego, CA · 92117

619-322-1454

David Howard Sitrick

Reg. 29349

Patent attorney

Sitrick & Sitrick

Pacific Palisades, CA · 90272

310-230-0606

Andrew D Sitzer

Reg. 53601

Patent agent

Sitzer Legal

Santa Ana, CA · 92701

323-309-9865

Michael A Sitzman

Reg. 42150

Patent attorney

McDermott Will & Emery

San Francisco, CA · 94105

628-218-3917

Harmonie M Siu

Reg. 73633

Patent agent

Emeryville, CA · 94608

510-697-4379

Neeraja Sivarajah

Reg. 64365

Patent attorney

Maxval Group Inc.

Los Altos, CA · 94024

650-472-0644

Kirsten Skaggs

Reg. 63894

Patent attorney

Palm Springs, CA · 92262

760-778-0400

Andrew D Skale

Reg. 44338

Patent attorney

Mintz, Levin, Cohn, Ferris, Glovsky

San Diego, CA · 92130

858-314-1500

Nicholas J Skarlatos

Reg. 37941

Patent attorney

Santa Clara, CA · 95054

408-512-1907

James P Skelley

Reg. 59458

Patent attorney

James Skelley

Mountain View, CA · 94040

650-281-2828

Kathleen Ann Skinner

Reg. 28476

Patent attorney

Beeson Skinner Beverly, LLP

Oakland, CA · 94612

510-832-8700

Jennifer A. Sklenar

Reg. 40205

Patent attorney

Arnold & Porter LLP

Los Angeles, CA · 90017

213-243-4000

Maya Skubatch

Reg. 52505

Patent attorney

Wilson Sonsini Goodrich and Rosati

Palo Alto, CA · 94304-1050

650-849-3330

Trina M Slabiak

Reg. 53602

Patent agent

San Francisco, CA · 94110

415-206-9333

Ann Reid Slaby

Reg. 54880

Patent attorney

Berkeley, CA · 94704

510-841-8755

Alexander P. Slafkosky

Reg. 73821

Patent attorney

Scale LLP

San Francisco, CA · 94114

443-904-1530

Jeffrey B Slaton

Reg. 48617

Patent attorney

California Dept. of Housing and Community

Sacramento, CA · 95814

916-321-7288

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.