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Dr. Mark L Geller, M.D.

Endocrinology, Diabetes & Metabolism Physician in Tarzana, CA · enumerated 2005.

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

National Provider Identifier

1093710345

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark L Geller
Credential M.D.
Sex Male
Practice address 18133 Ventura Blvd, Suite 204, Tarzana, CA, 91356
Phone (818) 466-7700
Fax (818) 996-1649
Enumeration date Jun 14, 2005
Last updated in NPPES Oct 23, 2018

Taxonomy & licenses

207RE0101X Endocrinology, Diabetes & Metabolism Physician Allopathic & Osteopathic Physicians · License G60287 (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
T0796 Other CA RAILROAD GROUP NUMBER
WG60287A Other CA MEDICARE RENDERING NUMBER
110061982 Other CA RAILROAD RENDERING NUMBER
YYY40048Y Medicaid CA -
95-3132732 Other CA BLUE CROSS OF CALIFORNIA
YYY40048Y Other CA BLUE SHIELD OF CALIFORNIA

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

Where does Mark Geller practice?
The practice location on file with NPPES is in Tarzana, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mark Geller?
The National Provider Identifier (NPI) for Mark Geller is 1093710345, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-10-23.