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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Marc H. Harwitt, M.D.

Gastroenterology Physician in Santa Monica, CA · enumerated 2006.

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

National Provider Identifier

1285613943

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Registry record

Entity type Individual (Type 1)
Name Dr. Marc H. Harwitt
Credential M.D.
Sex Male
Practice address 1301 20th St Ste 280, Santa Monica, CA, 90404
Phone (310) 829-6789
Fax (310) 935-3163
Enumeration date Jan 11, 2006
Last updated in NPPES Aug 28, 2020

Taxonomy & licenses

207RG0100X Gastroenterology Physician Allopathic & Osteopathic Physicians · License G23138 (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
00G231380 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

Is NPI 1285613943 active?
Yes, as of the latest NPPES snapshot, NPI 1285613943 is active (record last updated 2020-08-28).
How do I verify Marc Harwitt's NPI record?
Cross-check NPI 1285613943 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 2020-08-28.