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Individual
DR. JOHN STEPHEN HAMMES
Active
Individual
DR. JOHN STEPHEN HAMMES
Active
Sole proprietor
No
Provider details
NPI number
Gender
Man
Credential
M.D.
Taxonomy
Speciality
Code
Description
License number
State
207RN0300X
Nephrology Physician
Primary
G84351
CA
Other
Other identifiers
Code
Description
Identifier
Issuer
State
01
—
CA125550
NO CA MEDICARE PTAN
CA
01
—
CB204086
SO CA MEDICARE PTAN
CA
01
—
G84351
CA LICENSE
CA
Enumeration date
01/28/2006
Last updated
08/19/2026
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