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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Marc A Greer, DMD

General Practice Dentistry in Portsmouth, NH · enumerated 2006.

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

National Provider Identifier

1467476499

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Registry record

Entity type Individual (Type 1)
Name Dr. Marc A Greer
Credential DMD
Sex Male
Practice address Portsmouth, NH, 03801
Phone (603) 436-6922
Enumeration date Jul 26, 2006
Last updated in NPPES Dec 19, 2007

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

1223G0001X General Practice Dentistry Dental Providers · License 2326 (NH) Primary
DMD · Doctor of Medicine in Dentistry: A licensed dentist; DMD and DDS are equivalent dental degrees. About the DMD credential

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 1467476499 active?
Yes, as of the latest NPPES snapshot, NPI 1467476499 is active (record last updated 2007-12-19).
How do I verify Marc Greer's NPI record?
Cross-check NPI 1467476499 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 2007-12-19.