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, Quinn Emanuel Urquhart & Sullivan, LLP, and Messner Reeves LLP.

Top cities in California

All practitioners in California

Cameron D. Clawson

Reg. 73509

Patent attorney

Quinn Emanuel Urquhart & Sullivan, LLP

Redwood Shores, CA · 94065

650-801-5000

Allan B Claybon

Reg. 65797

Patent attorney

Messner Reeves LLP

Los Angeles, CA · 90025

424-276-6214

James P Cleary

Reg. 45843

Patent attorney

Mintz, Levin, Cohn, Ferris, Glovsky,

San Diego, CA · 92130

858-314-1500

Robert R. Cleary· Jr.

Reg. 60003

Patent attorney

Wilson Sonsini Goodrich & Rosati PC

Palo Alto, CA · 94304-1050

650-849-3252

Richard A Clegg

Reg. 33485

Patent attorney

Law Office of Richard Clegg

San Diego, CA · 92101

619-400-4920

Ken Clements

Reg. 77382

Patent agent

Los Gatos, CA · 95033

408-353-5027

Michael G Cleveland

Reg. 46030

Patent agent

Davis Wright Tremaine, LLP

San Francisco, CA · 94111-6533

415-276-6500

Carey J. Cling

Reg. 83011

Patent agent

Wilson Sonsini

San Diego, CA · 92130

858-350-2300

Tobi Carver Clinton

Reg. 43553

Patent attorney

Clinton Firm

Sacramento, CA · 95842

650-735-2137

Thomas James Clough

Reg. 22337

Patent attorney

Ensci INC

Grover Beach, CA · 93433

805-481-3750

Man Sung Co

Reg. 42423

Patent attorney

Cupertino, CA · 95014

408-316-9834

Morgan R. Coates

Reg. 64970

Patent attorney

Knobbe Martens Olson & Bear, LLP

Irvine, CA · 92614

949-760-0404

Ryan W. Cobb

Reg. 64598

Patent attorney

Okta

San Francisco, CA · 94105

888-722-7871

Cara M Coburn

Reg. 46631

Patent attorney

Genentech, Inc.

South San Francisco, CA · 94080

650-225-1000

H Adam Cochran

Reg. 29373

Patent attorney

California Institute of Technology

Pasadena, CA · 91125

626-395-4567

Keith M Cochran

Reg. 61480

Patent attorney

Chapin Fitzgerald LLP

San Diego, CA · 92101

619-241-4810

Samuel I. Cockriel

Reg. 77499

Patent attorney

Tarsus Pharmaceuticals, Inc.

Irvine, CA · 92618

949-418-1801

Sean M. Cody

Reg. 80467

Patent attorney

Carr & Ferrell LLP

Menlo Park, CA · 94025

650-812-3404

Allen B Coe

Reg. 51199

Patent attorney

United States Air Force

El Segundo, CA · 90245

310-633-3564

Dominic E.G. Coe

Reg. 57832

Patent agent

Davis, CA · 95616

530-750-0629

Donald James Coe

Reg. 56667

Patent agent

Donald James Coe, P.E.

Carmichael, CA · 95608

916-832-8963

Jaenam J. Coe

Reg. 68106

Patent attorney

Law Offices of Jaenam Coe PC

Los Angeles, CA · 90010

213-389-1400

Thomas Matthew Coester

Reg. 39637

Patent attorney

Thomas Coester Intellectual Property

Santa Monica, CA · 90409

310-584-7623

John M Coffey

Reg. 83715

Patent attorney

San Diego, CA · 92104

949-300-0236

Robert Philip Cogan

Reg. 25049

Patent attorney

Continuum Law

San Diego, CA · 92101

619-338-0400

Adrienne O. Cohen

Reg. 81228

Patent agent

Morrison Foerster LLC

San Francisco, CA · 94105

415-268-6854

David Menashi Cohen

Reg. 76314

Patent attorney

Knobbe Martens Olson & Bear, LLP

Irvine, CA · 92614

949-760-0404

David C Cohen

Reg. 43554

Patent agent

Cohen Patent Services

Oakland, CA · 94610

510-658-3039

Earl T. Cohen

Reg. 59638

Patent agent

etc Technologies, Inc.

Oakland, CA · 94618

408-209-8685

Howard Samuel Cohen

Reg. 27118

Patent agent

Berkeley, CA · 94707-2501

510-524-7733

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.