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Mark Horowitz Do, Inc.

Dermatology Physician in Torrance, CA · enumerated 2006 · authorized official Mark Horowitz, Owner.

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

National Provider Identifier

1952497414

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Registry record

Entity type Organization (Type 2)
Legal business name Mark Horowitz Do, Inc.
Practice address 23550 Hawthorne Blvd Ste 200, Torrance, CA, 90505
Phone (310) 373-2636
Enumeration date Oct 4, 2006
Last updated in NPPES May 23, 2011

Taxonomy & classification

207N00000X Dermatology Physician Allopathic & Osteopathic Physicians · License 20A7642 (CA) Primary
207ND0101X MOHS-Micrographic Surgery Physician Allopathic & Osteopathic Physicians · License 20A7642 (CA) Secondary
207ND0900X Dermatopathology Physician Allopathic & Osteopathic Physicians · License 20A7642 (CA) Secondary
207NI0002X Clinical & Laboratory Dermatological Immunology Physician Allopathic & Osteopathic Physicians · License 20A7642 (CA) Secondary
207NP0225X Pediatric Dermatology Physician Allopathic & Osteopathic Physicians · License 20A7642 (CA) Secondary
207NS0135X Procedural Dermatology Physician Allopathic & Osteopathic Physicians · License 20A7642 (CA) Secondary

Authorized official

Name Mark Horowitz
Title Owner
Phone (310) 373-2636

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 Horowitz Do, Inc.?
The NPI for Mark Horowitz Do, Inc. is 1952497414, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Mark Horowitz Do, Inc.?
NPPES lists Mark Horowitz (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 2011-05-23.