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Thomas D. Sullivan, MD, Sc

Specialist in Hinsdale, IL · enumerated 2006 · authorized official Thomas Sullivan, President.

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

National Provider Identifier

1366451742

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Registry record

Entity type Organization (Type 2)
Legal business name Thomas D. Sullivan, MD, Sc
Practice address 120 N Oak St, Neurophysiology Department, Hinsdale, IL, 60521
Phone (630) 574-0934
Fax (630) 574-0934
Enumeration date Aug 5, 2006
Last updated in NPPES May 20, 2008

Taxonomy & classification

174400000X Specialist Other Service Providers · License 036-043333 (IL) Primary

Authorized official

Name Thomas Sullivan
Title President
Phone (630) 574-0934

Other identifiers

Identifier Type State Issuer
036-043333 Medicaid IL -
02201078 Other IL 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

What is a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.
What type of organization is Thomas D. Sullivan, MD, Sc?
Thomas D. Sullivan, MD, Sc is registered in NPPES as a Specialist (its primary provider taxonomy).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-05-20.