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Mark J Stout, MD

Transplant Surgery Physician in Waukesha, WI · enumerated 2005.

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

National Provider Identifier

1851386551

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Registry record

Entity type Individual (Type 1)
Name Mark J Stout
Credential MD
Sex Male
Practice address 725 American Ave, Waukesha, WI, 53188
Phone (608) 263-1530
Enumeration date Sep 19, 2005
Last updated in NPPES May 3, 2021

Taxonomy & licenses

208G00000X Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician Allopathic & Osteopathic Physicians · License 01069517A (IN) Secondary
208G00000X Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician Allopathic & Osteopathic Physicians · License 62383 (WI) Secondary
208G00000X Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician Allopathic & Osteopathic Physicians · License 036080105 (IL) Secondary
204F00000X Transplant Surgery Physician Allopathic & Osteopathic Physicians · License 62383 (WI) 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
P01027332 Other IN RAILROAD MEDICARE
000001005823 Other IN ANTHEM PROVIDER NUMBER FOR TIN 35-2030653
036080105 Medicaid IL -
01605360 Other IL BCBS PROVIDER ID
201019900 Medicaid IN -
780000280 Other IL RAILROAD MEDICARE

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 this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Mark Stout?
Mark Stout is registered in NPPES with the primary taxonomy of Transplant Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2021-05-03.