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Stephen A. Weiss, MD

Internal Medicine Physician in Petaluma, CA · enumerated 2006 · practices at Kaiser Foundation Health Plan Inc.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1265516330

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Registry record

Entity type Individual (Type 1)
Name Stephen A. Weiss
Credential MD
Sex Male
Practice address 3900 Lakeville Hwy, Petaluma, CA, 94954
Phone (707) 765-3900
Enumeration date Oct 25, 2006
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License G63318 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
00G633180 Medicaid CA -

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.

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Frequently asked questions

What is the NPI number for Stephen Weiss?
The National Provider Identifier (NPI) for Stephen Weiss is 1265516330, a Type 1 (individual) record in the CMS NPPES registry.
Where does Stephen Weiss practice?
The practice location on file with NPPES is in Petaluma, CA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.