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 Bozicevic, Field & Francis LLC, Leonard Guzman, Esq., and ScienBiziP, P.C..

Top cities in California

All practitioners in California

Richard T Guy

Reg. 63623

Patent agent

Beaumont, CA · 92223

858-610-0259

Andrew R Guzman

Reg. 80613

Patent agent

Bozicevic, Field & Francis LLC

Redwood City, CA · 94061

650-833-7722

Leonard T Guzman

Reg. 46308

Patent attorney

Leonard Guzman, Esq.

Santa Barbara, CA · 93130

415-845-9358

Michael J Guzniczak

Reg. 59820

Patent attorney

ScienBiziP, P.C.

Los Angeles, CA · 90071

213-426-1780

William P. Gvoth

Reg. 74308

Patent attorney

QUALCOMM INCORPORATED

San Diego, CA · 92121

858-658-4780

Thomas O. Gwinn

Reg. 72497

Patent attorney

San Jose, CA · 95126-3159

650-383-8602

Jun S Ha

Reg. 58508

Patent attorney

Loza & Loza LLP

Upland, CA · 91786

877-406-5164

Michael B Ha

Reg. 39700

Patent attorney

Los Angeles, CA · 90007

949-235-2959

Elizabeth J Haanes

Reg. 42613

Patent attorney

IGM Biosciences, Inc.

Mountain View, CA · 94043

202-286-9629

Benjamin M Haber

Reg. 67129

Patent attorney

La Crescental, CA · 91214

818-624-9408

Brendan R. Haberle

Reg. 73325

Patent attorney

Dynavax

Emeryville, CA · 94608

877-848-5100

Sandra L Haberny

Reg. 64150

Patent attorney

Quinn Emanuel Urquhart & Sullivan LLP

Los Angeles, CA · 90017

213-443-3438

Guylaine Hache

Reg. 76083

Patent attorney

Amgen Inc.

Thousand Oaks, CA · 91320

312-324-1752

Christopher S. Hack

Reg. 82444

Patent attorney

DLA Piper

San Diego, CA · 92121

704-661-7951

Nora Ann Hackett

Reg. 33597

Patent agent

IP Support

Riverside, CA · 92508

951-776-9951

Walter A Hackler

Reg. 27792

Patent attorney

Patent Law Office

Newport Beach, CA · 92660

949-851-5010

Aubrey A. Haddach

Reg. 48374

Patent attorney

Halozyme Therapeutics , Inc.

San Diego, CA · 92130

858-204-6690

J David Hadden

Reg. 40629

Patent attorney

Fenwick and West, LLP

Mountain View, CA · 94041

650-988-8500

Peter Richard Haderlein

Reg. 71036

Patent agent

eSolar Inc.

Burbank, CA · 91510

818-303-9547

Frederick F Hadidi

Reg. 37342

Patent attorney

Turner Boyd Seraphine

San Mateo, CA · 94402

650-241-8181

Timothy J Hadlock

Reg. 35531

Patent attorney

East Palo Alto, CA · 94303

650-462-1049

Dino Hadzibegovic

Reg. 67775

Patent attorney

Dewey & LeBoeuf

San Francisco, CA · 94111

415-951-1112

James M Hafertepe

Reg. 51219

Patent attorney

One LLP

Newport Beach, CA · 92660

323-642-9206

Bejan Hafezzadeh

Reg. 76084

Patent attorney

ServiceNow

Santa Clara, CA · 95054

650-521-5390

Madjid Hafizi

Reg. 64769

Patent agent

San Diego, CA · 92129

858-780-1736

Robert W Haga

Reg. 41052

Patent agent

California Public Utilities Commission

San Francisco, CA · 94107

415-703-3700

Joseph M Hageman

Reg. 27897

Patent attorney

West Covina, CA · 91792

626-964-9769

Eric W Hagen

Reg. 44732

Patent attorney

McDermott Will & Emery LLP

Los Angeles, CA · 90067

310-277-4110

Jeffrey A Hagenah

Reg. 35175

Patent attorney

Portola Valley, CA · 94028

650-561-9714

Alicia Jean Hager

Reg. 44140

Patent attorney

Menlo Park, CA · 94025

650-644-8741

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.