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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Mrs. Rosemary S Marcus, MS, OTR/L

Specialist in Clinton, NY · enumerated 2011.

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

National Provider Identifier

1003183666

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Registry record

Entity type Individual (Type 1)
Name Mrs. Rosemary S Marcus
Credential MS, OTR/L
Sex Female
Practice address 102 College St, Clinton, NY, 13323
Enumeration date Nov 28, 2011
Last updated in NPPES Nov 28, 2011

Taxonomy & licenses

174400000X Specialist Other Service Providers · License 003388-1 (NY) Primary

Other identifiers

Identifier Type State Issuer
003388-1 Other NY NEW YORK STATE LICENSE TO PRACTICE OCCUPATIONAL THERAPY

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 Rosemary Marcus?
The National Provider Identifier (NPI) for Rosemary Marcus is 1003183666, a Type 1 (individual) record in the CMS NPPES registry.
Where does Rosemary Marcus practice?
The practice location on file with NPPES is in Clinton, NY. Providers can have multiple locations; NPPES lists the primary practice address.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-11-28.