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Mark Ensio Baker II

Neonatal-Perinatal Medicine Physician in Billings, MT · enumerated 2018.

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

National Provider Identifier

1538665187

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Registry record

Entity type Individual (Type 1)
Name Mark Ensio Baker II
Sex Male
Practice address 1233 N 30th St, Billings, MT, 59101
Phone (406) 237-7076
Enumeration date Apr 3, 2018
Last updated in NPPES Aug 29, 2024

Taxonomy & licenses

2080N0001X Neonatal-Perinatal Medicine Physician Allopathic & Osteopathic Physicians · License 142250 (MT) Primary

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

Is NPI 1538665187 active?
Yes, as of the latest NPPES snapshot, NPI 1538665187 is active (record last updated 2024-08-29).
How do I verify Mark Baker's NPI record?
Cross-check NPI 1538665187 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-08-29.