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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Gary Scott Tennyson, PH.D., M.D.

Anatomic Pathology & Clinical Pathology Physician in Shelton, CT · enumerated 2007 · practices at Dianon Systems, Inc.

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

National Provider Identifier

1659404481

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Registry record

Entity type Individual (Type 1)
Name Gary Scott Tennyson
Credential PH.D., M.D.
Sex Male
Practice address 1 Forest Pkwy, Shelton, CT, 06484
Phone (203) 926-7143
Enumeration date Mar 13, 2007
Last updated in NPPES Jan 13, 2009

Taxonomy & licenses

207ZP0102X Anatomic Pathology & Clinical Pathology Physician Allopathic & Osteopathic Physicians · License 040058 (CT) Primary
207ZP0102X Anatomic Pathology & Clinical Pathology Physician Allopathic & Osteopathic Physicians · License ME65534 (FL) Secondary
PHD · Doctor of Philosophy: A doctoral degree; in healthcare often held by clinical psychologists and researchers. About the PHD credential

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 NPI 1659404481 active?
Yes, as of the latest NPPES snapshot, NPI 1659404481 is active (record last updated 2009-01-13).
How do I verify Gary Tennyson's NPI record?
Cross-check NPI 1659404481 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-01-13.