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Dr. John K Berk, D.D.S.

General Practice Dentistry in Castro Valley, CA · enumerated 2006.

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

National Provider Identifier

1770507675

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Registry record

Entity type Individual (Type 1)
Name Dr. John K Berk
Credential D.D.S.
Sex Male
Practice address 20652 Redwood Rd, Castro Valley, CA, 94546
Phone (510) 733-6282
Fax (510) 733-6304
Enumeration date Jul 26, 2006
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

1223G0001X General Practice Dentistry Dental Providers · License 21540 (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

Where does John Berk practice?
The practice location on file with NPPES is in Castro Valley, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for John Berk?
The National Provider Identifier (NPI) for John Berk is 1770507675, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.