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William D. Mosier MD

Eyewear Supplier 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

1841542271

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Registry record

Entity type Organization (Type 2)
Legal business name William D. Mosier MD
Other name <Unavail>
Practice address 265 Laguna Rd, Fullerton, CA, 92835
Phone (714) 871-2570
Fax (714) 441-2020
Enumeration date Oct 9, 2012
Last updated in NPPES Nov 26, 2012

Taxonomy & classification

332H00000X Eyewear Supplier Suppliers · License A41428 (CA) Primary

Authorized official

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

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 type of organization is William D. Mosier MD?
William D. Mosier MD is registered in NPPES as a Eyewear Supplier (its primary provider taxonomy).
What is a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-11-26.