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Gregory J Diehl MD PC

Medical Specialty Clinic/Center in Port Jefferson Station, NY · enumerated 2011 · authorized official Gregory Diehl, President.

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

National Provider Identifier

1235436130

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Registry record

Entity type Organization (Type 2)
Legal business name Gregory J Diehl MD PC
Practice address 11 Medical Dr, Suite B, Port Jefferson Station, NY, 11776
Phone (631) 476-7300
Fax (631) 476-7304
Enumeration date Feb 12, 2011
Last updated in NPPES Feb 12, 2011

Taxonomy & classification

261QM2500X Medical Specialty Clinic/Center Ambulatory Health Care Facilities · License 1902162 (NY) Primary

Authorized official

Name Gregory Diehl
Title President
Phone (631) 476-7300

Other identifiers

Identifier Type State Issuer
1447249214 Other NY NPI

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 Gregory J Diehl MD PC?
Gregory J Diehl MD PC is registered in NPPES as a Medical Specialty 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 2011-02-12.