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William C Lyon MD, A Professional Corporation

Orthopaedic Surgery Physician in Pinole, CA · enumerated 2007 · authorized official William Lyon, Owner.

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

National Provider Identifier

1437359486

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Registry record

Entity type Organization (Type 2)
Legal business name William C Lyon MD, A Professional Corporation
Practice address 1700 San Pablo Ave, Suite A, Pinole, CA, 94564
Phone (510) 724-4113
Fax (510) 964-0607
Enumeration date Jul 18, 2007
Last updated in NPPES Sep 19, 2007

Taxonomy & classification

207X00000X Orthopaedic Surgery Physician Allopathic & Osteopathic Physicians · License G22328 (CA) Primary

Authorized official

Name William Lyon
Title Owner
Phone (510) 724-4113

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 C Lyon MD, A Professional Corporation?
The NPI for William C Lyon MD, A Professional Corporation is 1437359486, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for William C Lyon MD, A Professional Corporation?
NPPES lists William Lyon (Owner) as the authorized official for this organization.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-09-19.