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Mark T. Fahlen, MD, Inc. A Professional Medical Corporation

Nephrology Physician in Modesto, CA · enumerated 2008 · authorized official Mark Fahlen, President.

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

National Provider Identifier

1659537264

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Registry record

Entity type Organization (Type 2)
Legal business name Mark T. Fahlen, MD, Inc. A Professional Medical Corporation
Practice address 1400 Florida Ave, Suite 109, Modesto, CA, 95350
Phone (209) 544-2910
Fax (209) 544-2253
Enumeration date Aug 3, 2008
Last updated in NPPES Aug 2, 2011

Taxonomy & classification

207RN0300X Nephrology Physician Allopathic & Osteopathic Physicians · License A81212 (CA) Primary

Authorized official

Name Mark Fahlen
Title President
Phone (209) 544-2910

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 Mark T. Fahlen, MD, Inc. A Professional Medical Corporation?
The NPI for Mark T. Fahlen, MD, Inc. A Professional Medical Corporation is 1659537264, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Mark T. Fahlen, MD, Inc. A Professional Medical Corporation?
NPPES lists Mark Fahlen (President) as the authorized official for this organization.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-08-02.