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 JAMS, Riverbed Technology, Inc., and Intertrust Technologies Corporation.

Top cities in California

All practitioners in California

William F McDonald

Reg. 22777

Patent agent

JAMS

Orange, CA · 92868

714-318-3737

David P McDonough

Reg. 58166

Patent agent

Cupertino, CA · 95014

408-807-9639

Lawrence G McDonough

Reg. 55779

Patent attorney

San Diego, CA · 92163

858-354-1935

Melissa N McDonough

Reg. 64180

Patent attorney

Riverbed Technology, Inc.

San Francisco, CA · 94107

954-501-0664

Jeffery J McDow

Reg. 41982

Patent attorney

Intertrust Technologies Corporation

Sunnyvale, CA · 94085-3913

408-616-1616

Robert D McDowell

Reg. 59062

Patent attorney

HCL Technologies, Ltd.

Sunnyvale, CA · 94085

832-341-9985

Katharine E. McElhone

Reg. 57462

Patent attorney

Kura Oncology, Inc.

San Diego, CA · 92121

858-999-9999

Christopher R McElwain

Reg. 80967

Patent attorney

Knowmad Law

Monterey, CA · 93940

831-275-1401

Michael F McEntee

Reg. 28269

Patent attorney

Law Offices Of Michael McEntee

Huntington Beach, CA · 92649

714-307-9225

James David McFarland

Reg. 32544

Patent attorney

James D. McFarland

Cardiff, CA · 92007

858-357-5928

Robert A McFarlane

Reg. 56410

Patent attorney

Hanson Bridgett LLP

San Francisco, CA · 94105

415-995-5072

Thomas James McFarlane

Reg. 39299

Patent agent

Lumen Patent Firm

Palo Alto, CA · 94301

650-331-8412

Harry Vernon McGahey· Jr

Reg. 38240

Patent attorney

McGahey and McGahey, APLC

San Diego, CA · 92101

619-544-1888

Philip L McGarrigle

Reg. 31395

Patent attorney

Palo Alto, CA · 94303

650-494-3545

Mark W McGarry

Reg. 44918

Patent agent

San Diego, CA · 92130

858-229-9328

David R McGee

Reg. 41454

Patent agent

Vacaville, CA · 95687

707-448-3320

Sean P McGeehan

Reg. 48537

Patent attorney

AtaCor Medical, INC.

San Clemente, CA · 92672

949-482-1038

Joshua P. McGeorge

Reg. 76046

Patent agent

Davis, CA · 95616

520-390-7691

Michael B McGrath

Reg. 40083

Patent agent

Michael B. McGrath

Palo Alto, CA · 94306

650-493-6685

John P McGuire· Jr

Reg. 41984

Patent attorney

Oracle Corporation

Santa Clara, CA · 95054

408-276-7493

Karen B McGuirk

Reg. 52936

Patent agent

Thermo Fisher Scientific

Carlsbad, CA · 92008

425-507-5756

Harold Clayton McGurk· IV

Reg. 34964

Patent attorney

The Law Office of Clay McGurk

Orange, CA · 92856

949-395-3942

Aaron P McGushion

Reg. 53300

Patent agent

Seal Beach, CA · 90740

562-598-6418

Terri L McHenry

Reg. 55111

Patent attorney

Green Shoots Legal PC

Burlingame, CA · 94010

415-715-7578

Terry A. McHugh

Reg. 33261

Patent attorney

MOUNTAIN VIEW, CA · 94040

650-968-2225

Alistair J McIntyre

Reg. 77474

Patent attorney

Knobbe. Martens, Olson & Bear, LLP

Irvine, CA · 92614

206-405-2000

David Charles McIntyre

Reg. 36866

Patent attorney

Johnson & Johnson

Fremont, CA · 94555

510-248-2340

Joan V McIntyre

Reg. 33733

Patent attorney

Berkeley, CA · 94705

510-612-4096

Ian A. McKee

Reg. 60860

Patent attorney

Relativity Space

Long Beach, CA · 90807

415-866-0514

Robert C McKee

Reg. 69646

Patent agent

Davis, CA · 95616

512-203-5360

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.