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Charles Rosenbaum MD PC

Medical Oncology Physician in Marlborough, MA · enumerated 2007 · authorized official Charles Rosenbaum, Owner.

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

National Provider Identifier

1538285564

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Registry record

Entity type Organization (Type 2)
Legal business name Charles Rosenbaum MD PC
Practice address 65 Fremont St, Marlborough, MA, 01752
Phone (508) 481-4213
Fax (508) 481-7841
Enumeration date Mar 21, 2007
Last updated in NPPES Feb 19, 2008

Taxonomy & classification

207RX0202X Medical Oncology Physician Allopathic & Osteopathic Physicians · License 36848 (MA) Primary

Authorized official

Name Charles Rosenbaum
Title Owner
Phone (508) 481-4213

Other identifiers

Identifier Type State Issuer
2074303 Medicaid MA -

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 Charles Rosenbaum MD PC?
The NPI for Charles Rosenbaum MD PC is 1538285564, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Charles Rosenbaum MD PC?
NPPES lists Charles Rosenbaum (Owner) as the authorized official for this organization.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-02-19.