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Mark S. Feder, O.D.

Optometrist in Norwalk, CT · enumerated 2007 · authorized official Mark Feder, Owner.

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

National Provider Identifier

1487838082

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Registry record

Entity type Organization (Type 2)
Legal business name Mark S. Feder, O.D.
Practice address 5 Eversley Ave, Suite 104, Norwalk, CT, 06851
Phone (203) 853-1010
Fax (203) 866-0767
Enumeration date Dec 19, 2007
Last updated in NPPES Jun 16, 2008

Taxonomy & classification

152W00000X Optometrist Eye and Vision Services Providers · License 1047 (CT) Primary

Authorized official

Name Mark Feder
Title Owner
Phone (203) 853-1010

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 Mark S. Feder, O.D.?
Mark S. Feder, O.D. is registered in NPPES as a Optometrist (its primary provider taxonomy).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-06-16.