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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Gregory James Clark, LCSW-R

Clinical Social Worker in Olean, NY · enumerated 2006.

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

National Provider Identifier

1558449843

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Registry record

Entity type Individual (Type 1)
Name Gregory James Clark
Credential LCSW-R
Sex Male
Practice address Olean, NY, 14760
Phone (716) 378-1002
Fax (716) 373-2170
Enumeration date Nov 2, 2006
Last updated in NPPES Jul 8, 2007

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

1041C0700X Clinical Social Worker Behavioral Health & Social Service Providers · License R073675-1 (NY) Primary

Other identifiers

Identifier Type State Issuer
000590314001 Other NY BLUE CROSS BLUE SHIELD

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 Gregory Clark practice?
The practice location on file with NPPES is in Olean, NY. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Gregory Clark?
The National Provider Identifier (NPI) for Gregory Clark is 1558449843, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.