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Dr. Dianna Mung-Fung Mak, DO

Family Medicine Physician in Rancho Cucamonga, CA · enumerated 2006 · practices at Inland Physicians Service Inc.

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

National Provider Identifier

1104936988

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Registry record

Entity type Individual (Type 1)
Name Dr. Dianna Mung-Fung Mak
Credential DO
Sex Female
Practice address 9089 Baseline Road, Suite 100, Rancho Cucamonga, CA, 91730
Phone (909) 483-0505
Fax (909) 483-0508
Enumeration date Aug 30, 2006
Last updated in NPPES Jan 11, 2024

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 20A5237 (CA) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

Other identifiers

Identifier Type State Issuer
P00148996 Other CA RR MEDICARE
00AX52370 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 Dianna Mak's NPI record?
Cross-check NPI 1104936988 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1104936988 active?
Yes, as of the latest NPPES snapshot, NPI 1104936988 is active (record last updated 2024-01-11).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-01-11.