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Arnold Sterne Leff, MD

Family Medicine Physician in San Jose, CA · enumerated 2006.

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

National Provider Identifier

1326004730

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Registry record

Entity type Individual (Type 1)
Name Arnold Sterne Leff
Credential MD
Sex Male
Practice address 2400 Moorpark Ave, Internal Medicine Department, San Jose, CA, 95128
Phone (408) 885-5000
Enumeration date Apr 25, 2006
Last updated in NPPES May 7, 2018

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License C31564 (CA) Primary
207QG0300X Geriatric Medicine (Family Medicine) Physician Allopathic & Osteopathic Physicians · License C31564 (CA) Secondary
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
00C315640 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

How do I verify Arnold Leff's NPI record?
Cross-check NPI 1326004730 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1326004730 active?
Yes, as of the latest NPPES snapshot, NPI 1326004730 is active (record last updated 2018-05-07).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-05-07.