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Mark J Sontag MD

Pain Medicine (Physical Medicine & Rehabilitation) Physician in Redwood City, CA · enumerated 2006 · authorized official Mark Sontag, Owner.

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

National Provider Identifier

1639239528

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Registry record

Entity type Organization (Type 2)
Legal business name Mark J Sontag MD
Practice address 363 Main Street, C, Redwood City, CA, 94063
Phone (650) 306-9490
Fax (650) 306-0250
Enumeration date Dec 11, 2006
Last updated in NPPES Feb 1, 2008

Taxonomy & classification

2081P2900X Pain Medicine (Physical Medicine & Rehabilitation) Physician Allopathic & Osteopathic Physicians Primary

Authorized official

Name Mark Sontag
Title Owner
Phone (650) 306-9490

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 J Sontag MD?
The NPI for Mark J Sontag MD is 1639239528, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Mark J Sontag MD?
NPPES lists Mark Sontag (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 2008-02-01.