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Mark Brennan, DO

Vascular Surgery Physician in Johnson City, NY · enumerated 2005.

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

National Provider Identifier

1174523443

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Registry record

Entity type Individual (Type 1)
Name Mark Brennan
Credential DO
Sex Male
Practice address 30 Harrison St, Ste 455, Johnson City, NY, 13790
Phone (607) 763-8100
Fax (607) 763-8048
Enumeration date Jul 28, 2005
Last updated in NPPES Sep 15, 2014

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License 217717 (NY) Secondary
2086S0129X Vascular Surgery Physician Allopathic & Osteopathic Physicians · License 217717 (NY) 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
02082319 Medicaid NY -

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 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.
What specialty is Mark Brennan?
Mark Brennan is registered in NPPES with the primary taxonomy of Vascular Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-09-15.