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Robert C. Geiger, M. D., Professional Corporation

Medical Specialty Clinic/Center in Sonoma, CA · enumerated 2011 · authorized official Robert Geiger, Owner.

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

National Provider Identifier

1588932982

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Registry record

Entity type Organization (Type 2)
Legal business name Robert C. Geiger, M. D., Professional Corporation
Practice address 181 Andrieux St Ste 106, Sonoma, CA, 95476
Phone (707) 996-7077
Fax (707) 996-3723
Enumeration date Dec 13, 2011
Last updated in NPPES Dec 13, 2011

Taxonomy & classification

261QM2500X Medical Specialty Clinic/Center Ambulatory Health Care Facilities · License A17117 (CA) Primary

Authorized official

Name Robert Geiger
Title Owner
Phone (707) 996-7077

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 Robert C. Geiger, M. D., Professional Corporation?
Robert C. Geiger, M. D., Professional Corporation is registered in NPPES as a Medical Specialty Clinic/Center (its primary provider taxonomy).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-12-13.