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 Jackson and CO LLP, Cellanome, Inc., and Perkins Coie LLP.

Top cities in California

All practitioners in California

Kyong K OH

Reg. 54346

Patent agent

Jackson and CO LLP

Oakland, CA · 94611-2802

510-652-6418

Seong-Kun OH

Reg. 48210

Patent attorney

Jackson and CO LLP

Oakland, CA · 94611

510-652-6418

Timothy J Ohara

Reg. 53407

Patent attorney

Cellanome, Inc.

Foster City, CA · 94404

925-487-9963

Kenneth H Ohriner

Reg. 31646

Patent attorney

Perkins Coie LLP

Los Angeles, CA · 90067-1721

310-788-3267

Archana R Ojha

Reg. 53408

Patent attorney

San Francisco, CA · 94109

650-269-7664

James K Okamoto

Reg. 40110

Patent attorney

Saratoga, CA · 95070

408-255-0316

Michael S. Okamoto

Reg. 47831

Patent attorney

Los Angeles, CA · 90025

424-330-5642

David T Okano

Reg. 66657

Patent attorney

White & Case LLP

Palo Alto, CA · 94306

650-213-0363

Lynn K. Okuma

Reg. 79427

Patent agent

Encinitas, CA · 92023

858-354-5275

Victor Hayato Okumoto

Reg. 35973

Patent attorney

Fremont, CA · 94536

510-406-3975

Gabriel D. Olander

Reg. 59185

Patent attorney

Intuitive Surgical

Sunnyvale, CA · 94086

703-254-7246

Christian A Olano

Reg. 77325

Patent agent

Woodland Hills, CA · 91367

818-310-5070

David William Old

Reg. 77309

Patent agent

K&L Gates LLP

Irvine, CA · 92614

949-623-3557

Perry D Oldham

Reg. 52082

Patent attorney

Knobbe, Martens, Olson & Bear, LLP

Irvine, CA · 92614

949-721-2961

John Paul Oleksiuk

Reg. 67670

Patent attorney

Cooley LLP

Santa Monica, CA · 90401

310-883-6427

Nancy Ann Oleski

Reg. 34688

Patent attorney

Verdezyne Inc.

Carlsbad, CA · 92010

760-707-5244

Brian L Olion

Reg. 73054

Patent agent

Kilpatrick Townsend

Menlo Park, CA · 94025

650-324-6357

Sam Christopher Olive· III

Reg. 59903

Patent attorney

Splunk, Inc.

San Francisco, CA · 94107

415-266-3976

Erik L Oliver

Reg. 46296

Patent attorney

Redwood City, CA · 94065

650-267-0203

John William Olivo· Jr

Reg. 35634

Patent attorney

Olivo Patent Group

Beverly Hills, CA · 90210

310-562-1222

David E Olsen

Reg. 65584

Patent attorney

Olsen Patent Law

Petaluma, CA · 94952

408-230-5095

Eric J Olsen

Reg. 51157

Patent attorney

RPX Corporation

San Francisco, CA · 94105

415-728-9275

Joseph M. Olsen

Reg. 58764

Patent attorney

Salesforce.com

San Francisco, CA · 94105

415--83-6-3989

Kindon M. Olsen

Reg. 61887

Patent attorney

Murtaugh Meyer Nelson & Treglia LLP

Irvine, CA · 92614

949-794-4000

Kurt C Olsen

Reg. 29961

Patent attorney

Pleasanton, CA · 94566-8006

925-485-1981

Norman C Olsen

Reg. 42051

Patent attorney

Van Nuys, CA · 91411

818-785-2327

Stephen M. Olshemski

Reg. 80285

Patent attorney

Wilson, Sonsini, Goodriich and Rosati

Palo Alto, CA · 94304

570-690-1797

Darrell L Olson

Reg. 28247

Patent attorney

Darrell L. Olson Professional Corporation

Trabuco Canyon, CA · 92679

949-709-4588

Erica S Olson

Reg. 55927

Patent attorney

Amgen Inc., Law Department

Thousand Oaks, CA · 93120

805-447-3626

Jeffrey M Olson

Reg. 30790

Patent attorney

SOA LEGAL

Los Angeles, CA · 90017

213-200-4504

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.