Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Marc Joseph Clapper, D.O.

Anatomic Pathology & Clinical Pathology Physician in Johnstown, PA · enumerated 2007.

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

National Provider Identifier

1881711182

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)

Name Marc Joseph Clapper

Credential D.O.

Sex Male

Practice address 1086 Franklin St, Johnstown, PA, 15905

Phone (814) 534-9892

Fax (814) 534-9137

Enumeration date Mar 23, 2007

Last updated in NPPES Jan 29, 2023

Taxonomy & licenses

208D00000X General Practice Physician Allopathic & Osteopathic Physicians · License OT011820 (PA) Secondary

207ZP0102X Anatomic Pathology & Clinical Pathology Physician Allopathic & Osteopathic Physicians · License OS014283 (PA) 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

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.

Read the full guide → Validate an NPI →

Frequently asked questions

What specialty is Marc Clapper?

Marc Clapper is registered in NPPES with the primary taxonomy of Anatomic Pathology & Clinical Pathology Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-01-29.