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William D. Mosier, M.D.

Ophthalmology Physician in Fullerton, CA · enumerated 2012 · authorized official William Mosier, Owner/Physician.

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

National Provider Identifier

1679818264

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Registry record

Entity type Organization (Type 2)
Legal business name William D. Mosier, M.D.
Other name <Unavail>
Practice address 265 Laguna Rd, Fullerton, CA, 92835
Phone (714) 871-2570
Fax (714) 441-2020
Enumeration date Dec 7, 2012
Last updated in NPPES Dec 7, 2012

Taxonomy & classification

152W00000X Optometrist Eye and Vision Services Providers · License 10328T (CA) Secondary
152W00000X Optometrist Eye and Vision Services Providers · License 6488T (CA) Secondary
207W00000X Ophthalmology Physician Allopathic & Osteopathic Physicians · License A41428 (CA) Primary

Authorized official

Name William Mosier
Title Owner/Physician
Phone (714) 871-2570

Other identifiers

Identifier Type State Issuer
1063553378 Other CA INDIVIDUAL NPI

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 William D. Mosier, M.D.?
The NPI for William D. Mosier, M.D. is 1679818264, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for William D. Mosier, M.D.?
NPPES lists William Mosier (Owner/Physician) as the authorized official for this organization.

Providers at this address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-12-07.