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Cathy E Nieman, MD Inc

Internal Medicine Physician in Stillwater, OK · enumerated 2007 · authorized official Cathy Nieman, Medical Doctor.

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

National Provider Identifier

1588868327

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Registry record

Entity type Organization (Type 2)
Legal business name Cathy E Nieman, MD Inc
Other name <Unavail>
Practice address 821 S Walnut St, Stillwater, OK, 74074
Phone (405) 372-4646
Enumeration date Jun 14, 2007
Last updated in NPPES Nov 3, 2008

Taxonomy & classification

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 20253 (OK) Primary

Authorized official

Name Cathy Nieman
Title Medical Doctor
Phone (405) 372-4646

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

Who is the authorized official for Cathy E Nieman, MD Inc?
NPPES lists Cathy Nieman (Medical Doctor) as the authorized official for this organization.
What is the NPI number for Cathy E Nieman, MD Inc?
The NPI for Cathy E Nieman, MD Inc is 1588868327, a Type 2 (organization) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-11-03.