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 Waymo LLC, Kirkland & Ellis LLP, and Codexis, Inc..

Top cities in California

All practitioners in California

Sean B. Mackenzie

Reg. 70687

Patent attorney

San Clemente, CA · 92673

949-248-3080

Douglas E MacKenzie

Reg. 38955

Patent agent

Del Rey Oaks, CA · 93940

831-277-6181

Robert C MacKichan· III

Reg. 65262

Patent agent

Oakland, CA · 94611

202-815-3448

Alexander Fraser MacKinnon

Reg. 35594

Patent attorney

Kirkland & Ellis LLP

Los Angeles, CA · 90071

213-680-8432

Kamrin Terrell MacKnight

Reg. 38230

Patent attorney

Codexis, Inc.

Redwood City, CA · 94063

650-421-8138

Albert Macovski

Reg. 26564

Patent agent

Palo Alto, CA · 94304

650-473-9163

Bassil G. Madanat

Reg. 71765

Patent attorney

Pasadena, CA · 91101

909-215-6026

Erin Madden

Reg. 46892

Patent agent

The J David Gladstone Institutes

San Francisco, CA · 94141

415-695-3732

Marguerite M Maddux

Reg. 50962

Patent agent

Waymo LLC

Mountain View, CA · 94043

650-265-7617

Divya U. Madhyasta

Reg. 79968

Patent agent

Campbell, CA · 95008

408-242-5398

Eric L. Madigan

Reg. 76405

Patent attorney

Arent Fox LLP

Los Angeles, CA · 90013

213-443-7663

Amy C. Madl

Reg. 76529

Patent attorney

Amgen Inc.

South San Francisco, CA · 94080

650-680-5990

Rajeev Madnawat

Reg. 57190

Patent attorney

NXP Semiconductors

San Jose, CA · 95134

408-518-5534

Jeffrey Madrak

Reg. 74690

Patent agent

Santa Clara, CA · 95050

570-903-4748

Stuart J Madsen

Reg. 34381

Patent attorney

Granite Bay, CA · 95746

916-759-2587

Mayumi Maeda

Reg. 40075

Patent attorney

Johnson & Johnson

Milpitas, CA · 95035

408-956-4790

Zion D. Maffeo

Reg. 73269

Patent attorney

Waymo LLC

Mountain View, CA · 94043

844-420-0595

Robert S. Magee

Reg. 70227

Patent attorney

Blue Peak Law Group LLP

Palo Alto, CA · 94306

650-332-1701

Burt Magen

Reg. 37175

Patent attorney

Vierra Magen Marcus LLP

San Francisco, CA · 94105

415-489-4103

Taraneh Maghame

Reg. 43768

Patent attorney

Via Licensing Corporation

San Francisco, CA · 94103

415-645-4766

John D Magluyan

Reg. 56867

Patent agent

McDermott Will & Emery LLP

Irvine, CA · 92612-7108

949-757-7124

Thomas A Magnani

Reg. 45876

Patent attorney

Arnold & Porter LLP

San Francisco, CA · 94111

415-434-1600

Daniel Patrick Maguire

Reg. 41506

Patent attorney

Yolo Superior Court

Woodland, CA · 95695

530-406-6936

Victoria H Mah

Reg. 44889

Patent attorney

Cisco Systems, Inc.

San Jose, CA · 95134

408-853-9194

Zurvan Mahamedi

Reg. 42828

Patent attorney

Mahamedi IP Law LLP

Redwood City, CA · 94065

408-551-6632

Theresa J Mahan

Reg. 65086

Patent attorney

Theresa J Mahan

Fresno, CA · 93720

559-355-6746

F T Alexandra Mahaney

Reg. 37668

Patent attorney

Carefusion

San Diego, CA · 92130

858-617-2689

Tulip Mahaseth

Reg. 77201

Patent attorney

Synthego Corporation

Menlo Park, CA · 94025

650-251-1102

Ramin Mahboubian

Reg. 44890

Patent agent

Teradata Corporation

San Diego, CA · 92127

858-485-3645

David W Maher

Reg. 40077

Patent attorney

TechLaw LLP

San Diego, CA · 92131

858-228-7829

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.