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John Kok-Sen Chan, M.D.

Ophthalmology Physician in Union City, CA · enumerated 2007 · practices at Kaiser Foundation Health Plan Inc.

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

National Provider Identifier

1609928837

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Registry record

Entity type Individual (Type 1)
Name John Kok-Sen Chan
Credential M.D.
Sex Male
Practice address 3553 Whipple Rd, Union City, CA, 94587
Phone (510) 454-1000
Enumeration date Jan 17, 2007
Last updated in NPPES Dec 6, 2021

Taxonomy & licenses

207W00000X Ophthalmology Physician Allopathic & Osteopathic Physicians · License A70464 (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
00A704640 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

Where does John Chan practice?
The practice location on file with NPPES is in Union City, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for John Chan?
The National Provider Identifier (NPI) for John Chan is 1609928837, 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 2021-12-06.