NPI Portal NPI Lookup & Verification

Douglas Obrien

Douglas Obrien is a Physician Assistant provider (Physician Assistant) practicing in Greenbrae, CA, registered in the NPPES registry with NPI 1235158239 since 2006.

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NPI 1235158239
Entity type Individual (Type 1)
Name Douglas Obrien
Sex Male
Practice address 250 BON AIR RD, Greenbrae, CA, 94904
Phone 4159257000
Enumeration date 2006-07-19
Last updated in NPPES 2021-03-03

Taxonomy & licenses

Taxonomy code Specialty Primary License State
363A00000X Physician Assistant Primary PA13578 CA
Copy-ready billing details
Provider: Douglas Obrien
NPI: 1235158239
Taxonomy: 363A00000X (Physician Assistant)
Address: 250 BON AIR RD, Greenbrae, CA, 94904

Other providers at this practice address

NPI Name Type Specialty Location
1124021738 Marin Community Clinic Organization Federally Qualified Health Center (FQHC) Greenbrae, CA
1225031727 Aida Calvillo Individual Internal Medicine Physician Greenbrae, CA
1912900499 Debra Walhof Individual Pediatrics Physician Greenbrae, CA
1346249067 Georgianna Farren Individual Internal Medicine Physician Greenbrae, CA
1780677963 Janet Miller-Melka Individual Nurse Practitioner Greenbrae, CA
1538146337 Dana Huskey Individual Obstetrics & Gynecology Physician Greenbrae, CA
1679550032 Russell Fritz Individual Diagnostic Radiology Physician Greenbrae, CA
1396725677 Marin General Hospital Organization General Acute Care Hospital Greenbrae, CA

Verify this record

Cross-check NPI 1235158239 against the authoritative CMS record: view Douglas Obrien on the official NPPES registry .

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.

Frequently asked questions

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Douglas Obrien?
Douglas Obrien is registered in NPPES with the primary taxonomy of Physician Assistant. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2021-03-03.