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Mark E Bernthal, OD

Optometrist in St Clair Shores, MI · enumerated 2005.

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

National Provider Identifier

1811991391

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Registry record

Entity type Individual (Type 1)
Name Mark E Bernthal
Credential OD
Sex Male
Practice address 21711 Greater Mack Ave, St Clair Shores, MI, 48080
Enumeration date Jun 13, 2005
Last updated in NPPES Jun 11, 2008

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License 4901002685 (MI) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD credential

Other identifiers

Identifier Type State Issuer
0218080001 Other MI DMERC
410016688 Other MI MEDICARE RAILROAD

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

Is NPI 1811991391 active?
Yes, as of the latest NPPES snapshot, NPI 1811991391 is active (record last updated 2008-06-11).
How do I verify Mark Bernthal's NPI record?
Cross-check NPI 1811991391 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-06-11.