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Douglas Marx, D.O.

Family Medicine Physician in Germantown, WI · enumerated 2006.

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

National Provider Identifier

1326011321

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Registry record

Entity type Individual (Type 1)
Name Douglas Marx
Credential D.O.
Sex Male
Practice address W168n11237 Western Ave, Germantown, WI, 53022
Phone (262) 253-5060
Enumeration date Feb 9, 2006
Last updated in NPPES Feb 3, 2014

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 40581 (WI) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

Other identifiers

Identifier Type State Issuer
30096200 Medicaid WV -

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 Douglas Marx practice?
The practice location on file with NPPES is in Germantown, WI. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Douglas Marx?
The National Provider Identifier (NPI) for Douglas Marx is 1326011321, 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 2014-02-03.