NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Mr. Mark Gillespie, P.A.

Physician Assistant in Greenbrae, CA · enumerated 2009.

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

National Provider Identifier

1609104835

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Registry record

Entity type Individual (Type 1)
Name Mr. Mark Gillespie
Credential P.A.
Sex Male
Practice address 250 Bon Air Rd, Greenbrae, CA, 94904
Phone (415) 925-7000
Fax (415) 925-7555
Enumeration date Nov 30, 2009
Last updated in NPPES May 29, 2026

Taxonomy & licenses

363A00000X Physician Assistant Physician Assistants & Advanced Practice Nursing Providers · License PA58005 (CA) Primary
PA · Physician Assistant: A licensed clinician who practices medicine in collaboration with physicians, trained in a graduate PA program. About the PA credential

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

Is NPI 1609104835 active?
Yes, as of the latest NPPES snapshot, NPI 1609104835 is active (record last updated 2026-05-29).
How do I verify Mark Gillespie's NPI record?
Cross-check NPI 1609104835 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2026-05-29.