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Dr. Gregory Mark Silva, OD

Optometrist in Antioch, CA · enumerated 2007 · practices at Kaiser Foundation Health Plan Inc.

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

National Provider Identifier

1285786012

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Registry record

Entity type Individual (Type 1)
Name Dr. Gregory Mark Silva
Credential OD
Sex Male
Practice address 3400 Delta Fair Blvd, Antioch, CA, 94509
Phone (925) 779-5000
Enumeration date Jan 18, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License 5599T (CA) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD credential

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

What is the NPI number for Gregory Silva?
The National Provider Identifier (NPI) for Gregory Silva is 1285786012, a Type 1 (individual) record in the CMS NPPES registry.
Where does Gregory Silva practice?
The practice location on file with NPPES is in Antioch, CA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.