John K. Berk, D.D.S.
General Practice Dentistry · Castro Valley, CA
John K. Berk, D.D.S. is a general practice dentistry with a practice address in Castro Valley, California, and NPI 1770507675, issued on Jul 26, 2006. Check the license (California 21540, as entered in NPPES) with the California board that licenses this profession; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- John K. Berk
- Credential
- D.D.S.
- Primary taxonomy
- General Practice Dentistry 1223G0001X
- License number
- 21540 CA
Self-reported in NPPES; status is on the state search - Practice location
- 20652 Redwood RD, Castro Valley, CA 94546
- Phone
- (510) 733-6282
- Enumerated
- Jul 26, 2006
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (510) 733-6304
- Entity
- Type 1 · individual
8 nearest general practice dentistry records → All 17,852 in California → Look up another NPI →
Also registered at 20652 Redwood RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Hoa Lai, DDSDentist1922197748
Verify John K. Berk in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich California board licenses this profession
Search for license 21540Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
John K. Berk among 17,852 general practice dentistry records in California
John K. Berk, D.D.S. is one of 17,852 general practice dentistry records with a practice address in California. 57% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2006, is newer than 3% of them.
- NPI issued2006 · 3% of these records are older, 71% newer
- In a Medicare fileNo · 57% of these records are
- In the CMS Doctors and Clinicians fileNo · under 1% of these records are
- Record last updated2007 · 79% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 1223G0001X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
24 general practice dentistry records list a practice address in Castro Valley
They are 24 of the 999 NPPES records with a practice address in Castro Valley, and 17,852 general practice dentistry records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 17,852 in California → Every provider in Castro Valley → General Practice Dentistry nationwide →
The 8 general practice dentistry records with the nearest ZIP codes
- Bruce Ahtye, D.D.S.Castro Valley, CA 945461528147600
- Robert Darnell, D.D.S.Castro Valley, CA 945461144316993
- Jeffrey Erickson, D.D.SCastro Valley, CA 945461053451435
- Gregory Hong, D.D.S.Castro Valley, CA 945461912051905
- Robert Maass, DDSCastro Valley, CA 945461205989415
- George Mackenzie, DDSCastro Valley, CA 945461114070315
- Robert Oneill, DDSCastro Valley, CA 945461659593366
- Shirin Salehinia, D.D.SCastro Valley, CA 945461851444962
Common questions
What is John K. Berk, D.D.S.'s NPI number?
John K. Berk, D.D.S.'s National Provider Identifier (NPI) is 1770507675, issued on Jul 26, 2006. An NPI identifies a provider in billing; it is not a license.
Where is John K. Berk, D.D.S. located?
The NPPES record lists a practice address at 20652 Redwood RD, Castro Valley, CA, 94546. Phone: (510) 733-6282. Providers update this record themselves, so call before visiting.
How can I verify John K. Berk, D.D.S.'s license?
NPPES lists California license number 21540, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.