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Dr. Catharine Teresa Clark-Sayles, M.D.

Internal Medicine Physician in Greenbrae, CA · enumerated 2005.

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

National Provider Identifier

1518952860

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Registry record

Entity type Individual (Type 1)
Name Dr. Catharine Teresa Clark-Sayles
Credential M.D.
Sex Female
Practice address 1341 S Eliseo Dr, Suite 200, Greenbrae, CA, 94904
Phone (415) 464-8176
Fax (415) 464-8177
Enumeration date Sep 13, 2005
Last updated in NPPES Jun 23, 2009

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License G49182 (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
00G491820 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.

Read the full guide → Validate an NPI →

Frequently asked questions

What specialty is Catharine Clark-Sayles?
Catharine Clark-Sayles is registered in NPPES with the primary taxonomy of Internal Medicine Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
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.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-06-23.