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 Law Office of Benjamin Diederich, Diadexus, and Bozicevic, Field & Francis LLP.

Top cities in California

All practitioners in California

Benjamin N Diederich

Reg. 54067
Patent attorney

Law Office of Benjamin Diederich

Menifee, CA · 92586

951-332-7079

Gundo Diedrich

Reg. 55113
Patent agent

Diadexus

South San Francisco, CA · 94080-1913

650-246-6481

James J Diehl

Reg. 47527
Patent attorney

Bozicevic, Field & Francis LLP

Redwood City, CA · 94065

650-327-3400

Michael R Diekmann

Reg. 51617
Patent attorney

Lancaster, CA · 93536

661-275-7100

Louis Diep

Reg. 57778
Patent attorney

Nokia

Sunnyvale, CA · 94085

408-203-8397

Anthony B Diepenbrock· III

Reg. 39960
Patent attorney

San Jose, CA · 95120

408-927-9654

Michael P Dierks

Reg. 38857
Patent attorney

San Francisco, CA · 94118

408-314-8239

Ethan M Dietrich

Reg. 56949
Patent attorney

Los Angeles, CA · 90068

215-805-3856

Peter S. Diez

Reg. 76132
Patent agent

Sheppard Mullin

Palo Alto, CA · 94301

650-815-1939

Manali V Dighe

Reg. 56856
Patent attorney

Santa Cruz, CA · 95060

707-731-3817

Christopher M. DiLeo

Reg. 61738
Patent attorney

Becton, Dickinson and Company

San Diego, CA · 92130

858-617-3933

Nathaniel L Dilger

Reg. 42485
Patent attorney

O'Melveny & Myers LLP

Newport Beach, CA · 92660

949-760-9600

David A Dillard

Reg. 30831
Patent attorney

Christie Parker & Hale, LLP

Glendale, CA · 91203-1445

626-795-9900

Thomas R Dillof

Reg. 63900
Patent attorney

San Diego, CA · 92104

646-729-4085

Harrison F Dillon

Reg. 45661
Patent agent

Solazyme, Inc.

South San Francisco, CA · 94080

650-780-4778

Samuel A Dillon

Reg. 65197
Patent attorney

Apple Inc.

Cupertino, CA · 95014

408-529-2393

Guy J. DiMauro

Reg. 79745
Patent agent

Beckman Coulter

Brea, CA · 92821

949-291-3516

Yekun Ding

Reg. 78699
Patent agent

Santa Cruz, CA · 95064

831-502-1398

Yi Ding

Reg. 65025
Patent agent

San Jose, CA · 95111

408-585-8140

Joshua S Dingott

Reg. 69540
Patent attorney

Hewlett Packard Enterprise

Palo Alto, CA · 94304

512-319-0257

Chi N Dinh

Reg. 68413
Patent attorney

Hayward, CA · 94545

510-786-1871

Truong Dinh

Reg. 40993
Patent agent

Dinh & Associates

Penngrove, CA · 94951

650-289-0600

Peter W Dini

Reg. 52821
Patent attorney

Sorrento

San Diego, CA · 92121

617-320-3360

Alanna N. Dion

Reg. 58745
Patent attorney

Tailored Shared Services, LLC.

Fremont, CA · 94538

510-723-8641

Christen G DiPetrillo

Reg. 73789
Patent attorney

Parker Institute for Cancer Immunotherapy

San Francisco, CA · 94129

628-899-7600

Eric A Dippel

Reg. 48890
Patent attorney

Campbell, CA · 95008

408-370-3624

Sara E Dirvianskis

Reg. 62613
Patent agent

Danville, CA · 94526

925-408-3365

Charles E Dispenzieri

Reg. 71931
Patent attorney

Sempra Energy

San Diego, CA · 92101

619-696-4856

Michael J Dix

Reg. 51621
Patent agent

San Jose, CA · 95124

408-267-0139

Cynthia Anne Dixon

Reg. 58926
Patent attorney

Polsinelli LLP

Los Angeles, CA · 90067

310-203-5355

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.
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