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

Stephen Martin Knox, MD

Internal Medicine Physician in Oakland, CA · enumerated 2006.

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

National Provider Identifier

1255439345

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Registry record

Entity type Individual (Type 1)
Name Stephen Martin Knox
Credential MD
Sex Male
Practice address Oakland, CA, 94609
Phone (510) 628-0949
Fax (510) 628-0947
Enumeration date Sep 20, 2006
Last updated in NPPES May 8, 2024

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

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License G063555 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
00G063555 Medicaid CA -

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 Stephen Knox practice?
The practice location on file with NPPES is in Oakland, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Stephen Knox?
The National Provider Identifier (NPI) for Stephen Knox is 1255439345, 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 2024-05-08.