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William W. Kirby, M.D.

Specialist in Auburn, CA · enumerated 2010 · authorized official William Kirby, Owner.

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

National Provider Identifier

1023329257

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Registry record

Entity type Organization (Type 2)
Legal business name William W. Kirby, M.D.
Practice address 3257 Professional Dr, Suite D, Auburn, CA, 95602
Phone (530) 823-6500
Fax (530) 823-8568
Enumeration date Jun 22, 2010
Last updated in NPPES May 11, 2015

Taxonomy & classification

174400000X Specialist Other Service Providers · License G334720 (CA) Primary

Authorized official

Name William Kirby
Title Owner
Phone (530) 823-6500

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 current is this record?
Data comes from the CMS NPPES public dissemination file; this record was last updated in NPPES on 2015-05-11. Verify at npiregistry.cms.hhs.gov.
Where is William W. Kirby, M.D. located?
The practice location on file with NPPES is in Auburn, CA.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2015-05-11.