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 Morrison & Foerster LLP, Law Offices of M. E. Cavanaugh, and Henderson and Caverly LLP.

Top cities in California

All practitioners in California

Marion E. Cavanaugh

Reg. 40550

Patent attorney

Law Offices of M. E. Cavanaugh

Mountain View, CA · 94043

650-533-4363

Matthew E Cavanaugh

Reg. 55042

Patent attorney

Long Beach, CA · 90804-4052

562-328-4673

Kristen E Caverly

Reg. 47477

Patent attorney

Henderson and Caverly LLP

Rancho Santa Fe, CA · 92067

858-756-6345

Michael Caywood

Reg. 37797

Patent attorney

Globalfoundries US Inc.

Santa Clara, CA · 95054

408-462-4700

Emilio A. Cazares

Reg. 76540

Patent agent

Sheppard Mullin Richter & Hampton LLP

San Diego, CA · 92130

619-720-7459

Thomas G Cehelnik

Reg. 71432

Patent agent

Irvine, CA · 92618

408-338-5125

James J Cekola

Reg. 63720

Patent agent

Morrison & Foerster LLP

San Diego, CA · 92130

760-672-0974

Krista A Celentano

Reg. 66981

Patent attorney

DLA Piper LLP (USA)

East Palo Alto, CA · 94303

650-833-2171

Rosemarie L Celli

Reg. 42397

Patent attorney

Alston & Bird LLP

East Palo Alto, CA · 94303

650-838-2000

Robert K Cerpa

Reg. 39933

Patent agent

Morrison & Foerster LLP

Palo Alto, CA · 94304

650-813-5715

Kimberlie L Cerrone

Reg. 37111

Patent attorney

Law Office of Kimberlie L. Cerrone

San Francisco, CA · 94158

415-378-2838

Nicholas D. Cervenka

Reg. 81893

Patent agent

Bozicevic, Field & Francis LLP

San Francisco, CA · 94105

415-230-8100

Taian Cha

Reg. 57288

Patent agent

Talan Cha

Tracy, CA · 95304

209-229-1179

Ralph D Chabot

Reg. 39133

Patent attorney

Law Office of Ralph D. Chabot

Camarillo, CA · 93010

805-388-5028

William B Chadwick

Reg. 76073

Patent attorney

Loza & Loza LLP

Upland, CA · 91786

385-401-0465

Heedong Chae

Reg. 69240

Patent attorney

East West Law Group, PC

Los Angeles, CA · 90010

213-387-3630

Isabelle Chae

Reg. 83114

Patent attorney

Tiburon, CA · 94920

415-504-2075

Kenneth G Chahine

Reg. 42398

Patent attorney

Avigen, Inc.

Alameda, CA · 94502

510-748-7154

Calvin H Chai

Reg. 68009

Patent attorney

ScienBiziP, P.C.

Los Angeles, CA · 90071

213-426-1779

Johnathan L Chai

Reg. 75690

Patent agent

Fenwick & West LLP

Mountain View, CA · 94041

650-335-7804

Stephen Chai

Reg. 69569

Patent agent

Lee & Advocates

Los Angeles, CA · 90010

213-905-0618

Yar R Chaikovsky

Reg. 39625

Patent attorney

Paul Hastings LLP

Palo Alto, CA · 94304

650-820-1832

Amrita Chakrabarti

Reg. 72736

Patent agent

Lewis Roca Rothgerber Christie LLP

Glendale, CA · 91203-1445

626-683-4559

Pallab Chakraborty

Reg. 72007

Patent attorney

Xilinx, Inc.

San Jose, CA · 95124-3400

408-879-5036

Akshay S Chakravarthy

Reg. 64708

Patent agent

Oak Park, CA · 91377

818-618-7055

Daniel M Chambers

Reg. 34561

Patent attorney

Acuity Law Group, P.C.

San Diego, CA · 92130

858-350-9690

Elaina M. Chambers

Reg. 78674

Patent agent

San Jose, CA · 95123

502-494-3185

Guy Wayne Chambers

Reg. 30617

Patent attorney

Sideman & Bancroft LLP

San Francisco, CA · 94111

415-733-3950

Stephanie A Chambers

Reg. 58034

Patent agent

Santa Monica, CA · 90404

310-403-1640

Beau D. Champ

Reg. 82754

Patent agent

Ventura, CA · 93004

812-320-7908

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.