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Thomas Paul Marnejon, DO

Internal Medicine Physician in Youngstown, OH · enumerated 2006.

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

National Provider Identifier

1891898607

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Registry record

Entity type Individual (Type 1)
Name Thomas Paul Marnejon
Credential DO
Sex Male
Practice address 1001 Covington St, Youngstown, OH, 44510
Phone (330) 480-2616
Fax (330) 480-7979
Enumeration date Sep 7, 2006
Last updated in NPPES Apr 13, 2019

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 34004912 (OH) Primary
DO — Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

Other identifiers

Identifier Type State Issuer
H143790 Other OH MEDICARE PTAN
0866013 Medicaid OH —

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 1891898607 active?
Yes — as of the latest NPPES snapshot, NPI 1891898607 is active (record last updated 2019-04-13).
How do I verify Thomas Marnejon's NPI record?
Cross-check NPI 1891898607 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 2019-04-13.