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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Mark Richard Koenen, DDS

General Practice Dentistry in Danville, CA · enumerated 2006.

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

National Provider Identifier

1023111952

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark Richard Koenen
Credential DDS
Sex Male
Practice address Danville, CA, 94526
Phone (925) 837-6318
Fax (925) 837-4992
Enumeration date Sep 6, 2006
Last updated in NPPES Nov 7, 2012

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

1223G0001X General Practice Dentistry Dental Providers · License 36780 (CA) Primary
DDS · Doctor of Dental Surgery: A licensed dentist; DDS and DMD are equivalent dental degrees. About the DDS credential

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

How do I verify Mark Koenen's NPI record?
Cross-check NPI 1023111952 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1023111952 active?
Yes, as of the latest NPPES snapshot, NPI 1023111952 is active (record last updated 2012-11-07).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-11-07.