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 Key Kesan Dallmann PLLC, Law Office of Philip Dalton, and Lewis Roca Rothgerber Christie LLP.

Top cities in California

All practitioners in California

Ken B Dallara

Reg. 51118

Patent attorney

Simi Valley, CA · 93063

805-297-4510

Andrew S Dallmann

Reg. 55096

Patent attorney

Key Kesan Dallmann PLLC

Laguna Hills, CA · 92653

951-678-2267

Christian Taylor Dalton

Reg. 58362

Patent attorney

Los Angeles, CA · 90048

202-316-1139

Philip Arthur Dalton· Jr

Reg. 26859

Patent attorney

Law Office of Philip Dalton

San Francisco, CA · 94127

415-505-0716

Thomas James Daly

Reg. 32213

Patent attorney

Lewis Roca Rothgerber Christie LLP

Glendale, CA · 91203-1445

626-795-9900

Reid Eric Dammann

Reg. 57227

Patent attorney

Gordon & Rees LLP

San Diego, CA · 92101

619-696-6700

Jubin Dana

Reg. 41400

Patent attorney

Dana Legal Services

Menlo Park, CA · 94025

650-387-0003

James C Danaher

Reg. 61842

Patent attorney

Gordon Rees Scully Mansukhani, LLP

San Diego, CA · 92101

619-696-6700

Eugene D Daneshvar

Reg. 77545

Patent agent

Wilson Sonsini Goodrich & Rosati, P.C.

Palo Alto, CA · 94304-1050

650-565-3775

David V. Dang

Reg. 60071

Patent agent

Mintz Levin Cohn Ferris Glovsky and Popeo PC

San Diego, CA · 92130

858-314-1500

Lan C Dang

Reg. 55797

Patent attorney

Beverly Hills, CA · 90212

310-777-8399

Sang N Dang

Reg. 51186

Patent attorney

Blue Captial Law Firm, P.C.

Coasta Mesa, CA · 92626

714-839-3800

Tri Cao Dang

Reg. 71853

Patent attorney

Womble Bond Dickinson LLP

Costa Mesa, CA · 92626

714-557-3800

Andy G. Daniel

Reg. 84255

Patent agent

South San Francisco, CA · 94080

917-780-6935

Adam P Daniels

Reg. 66681

Patent attorney

Polsinelli LLP

Los Angeles, CA · 90067

310-556-6754

Blake E Daniels

Reg. 78175

Patent agent

Metagenomi

Emeryville, CA · 94608

740-504-7386

Mark J Danielson

Reg. 40580

Patent attorney

Foley & Lardner LLP

Palo Alto, CA · 94304

650-251-1159

Richard Arthur Dannells· Jr

Reg. 22654

Patent attorney

Manatt Phelps Phillips LLP

Palo Alto, CA · 94304

805-773-1181

Allen Dale Danner

Reg. 60958

Patent attorney

Danner IP Law Firm

Arcadia, CA · 91066-1930

213-448-8668

Douglas H. Danner

Reg. 73014

Patent attorney

Haynes and Boone, LLP

Costa Mesa, CA · 92626

949-202-3081

Alexander T. K. Dao

Reg. 81096

Patent agent

Irvine, CA · 92603

949-812-9705

Mimi-Diemmy Dao

Reg. 45628

Patent attorney

Applied Materials, Inc.

Santa Clara, CA · 95054

408-235-4902

Nicholas T. K. Dao

Reg. 83972

Patent agent

Irvine, CA · 92603

949-433-1347

Tom H Dao

Reg. 44641

Patent attorney

ALUMEN IP Law PC

Irvine, CA · 92618

949-368-2270

Abdul A Darab

Reg. 64839

Patent agent

Pasadena, CA · 91101

626-768-4485

John R. Darakjian

Reg. 71902

Patent attorney

Encino, CA · 91436

818-317-2192

Joseph-Stephen M DaRe

Reg. 42463

Patent agent

Neurocrine Biosciences, Inc.

San Diego, CA · 92130

858-617-7777

Rudolph P Darken

Reg. 77988

Patent attorney

JRG Attorneys At Law

Salinas, CA · 93901

831-457-2444

Christopher Darrow

Reg. 30166

Patent attorney

Santa Monica, CA · 90402

310-717-7813

Jill C Darsow

Reg. 71968

Patent attorney

Walnut Creek, CA · 94598

925-584-7718

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.