NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Mason H Weiss, M.D.

Specialist in Inglewood, CA · enumerated 2005.

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

National Provider Identifier

1447256565

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Registry record

Entity type Individual (Type 1)
Name Dr. Mason H Weiss
Credential M.D.
Sex Male
Practice address 501 E Hardy St, Ste 200, Inglewood, CA, 90301
Phone (310) 672-3900
Fax (310) 671-8438
Enumeration date Jun 23, 2005
Last updated in NPPES Nov 10, 2021

Taxonomy & licenses

174400000X Specialist Other Service Providers · License G44527 (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
00G445270 Medicaid CA -
95-4170981 Other CA GROUP PROVIDER ID
G44527 Other CA MEDICAL LICENSE

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 1447256565 active?
Yes, as of the latest NPPES snapshot, NPI 1447256565 is active (record last updated 2021-11-10).
How do I verify Mason Weiss's NPI record?
Cross-check NPI 1447256565 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 2021-11-10.