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Willam H Marks, MD

Transplant Surgery Physician in Seattle, WA · enumerated 2006.

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

National Provider Identifier

1942365705

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Registry record

Entity type Individual (Type 1)
Name Willam H Marks
Credential MD
Sex Male
Practice address 1101 Madison St, Ste 200, Seattle, WA, 98104
Phone (206) 386-3660
Fax (206) 386-3644
Enumeration date Dec 22, 2006
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

204F00000X Transplant Surgery Physician Allopathic & Osteopathic Physicians · License MD00031116 (WA) 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
8149320 Medicaid WA -

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 Willam Marks practice?
The practice location on file with NPPES is in Seattle, WA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Willam Marks?
The National Provider Identifier (NPI) for Willam Marks is 1942365705, 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 2007-07-08.