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Peter J Siefken, PA

Medical Physician Assistant in Amagansett, NY · enumerated 2007 · practices at Sports Physical Therapy East, PC.

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

National Provider Identifier

1144347261

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Registry record

Entity type Individual (Type 1)
Name Peter J Siefken
Credential PA
Sex Male
Practice address 518 Montauk Hwy, Ste 102, Amagansett, NY, 11930
Phone (631) 267-5373
Fax (631) 267-5376
Enumeration date Mar 23, 2007
Last updated in NPPES Dec 5, 2016

Taxonomy & licenses

363AM0700X Medical Physician Assistant Physician Assistants & Advanced Practice Nursing Providers · License 005732 (NY) Primary
PA · Physician Assistant: A licensed clinician who practices medicine in collaboration with physicians, trained in a graduate PA program. About the PA credential

Other identifiers

Identifier Type State Issuer
02175175 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

Where does Peter Siefken practice?
The practice location on file with NPPES is in Amagansett, NY. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Peter Siefken?
The National Provider Identifier (NPI) for Peter Siefken is 1144347261, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2016-12-05.