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Brightwaters Internal Medicine Pllc

Sleep Medicine (Internal Medicine) Physician in Bay Shore, NY · enumerated 2007 · authorized official Mark Siegelheim, Physician.

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

National Provider Identifier

1255533360

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Registry record

Entity type Organization (Type 2)
Legal business name Brightwaters Internal Medicine Pllc
Practice address 200 Howells Rd, Bay Shore, NY, 11706
Phone (631) 665-5074
Fax (631) 665-1852
Enumeration date Jun 1, 2007
Last updated in NPPES Aug 22, 2020

Taxonomy & classification

207RS0012X Sleep Medicine (Internal Medicine) Physician Allopathic & Osteopathic Physicians · License 152199 (NY) Primary

Authorized official

Name Mark Siegelheim
Title Physician
Phone (631) 665-5074

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 the NPI number for Brightwaters Internal Medicine Pllc?
The NPI for Brightwaters Internal Medicine Pllc is 1255533360, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Brightwaters Internal Medicine Pllc?
NPPES lists Mark Siegelheim (Physician) as the authorized official for this organization.

Providers at this address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-08-22.