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Mark Tieman, MD, PC

Primary Care Clinic/Center in Commack, NY · enumerated 2011 · authorized official Mark Tieman, President.

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

National Provider Identifier

1821375940

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Registry record

Entity type Organization (Type 2)
Legal business name Mark Tieman, MD, PC
Practice address 356 Veterans Memorial Hwy, Commack, NY, 11725
Phone (631) 858-0400
Fax (631) 543-2785
Enumeration date Nov 3, 2011
Last updated in NPPES Nov 3, 2011

Taxonomy & classification

261QP2300X Primary Care Clinic/Center Ambulatory Health Care Facilities · License 179172 (NY) Primary

Authorized official

Name Mark Tieman
Title President
Phone (631) 424-9844

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

What is a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.
What type of organization is Mark Tieman, MD, PC?
Mark Tieman, MD, PC is registered in NPPES as a Primary Care Clinic/Center (its primary provider taxonomy).

Providers at this address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-11-03.