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Arthur David Siek, M.D.

Hospitalist Physician in Olympia, WA · enumerated 2008.

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

National Provider Identifier

1326223801

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Registry record

Entity type Individual (Type 1)
Name Arthur David Siek
Credential M.D.
Sex Male
Practice address 413 Lilly Road Ne, Olympia, WA, 98506
Phone (360) 491-9480
Enumeration date Jan 3, 2008
Last updated in NPPES Mar 11, 2008

Taxonomy & licenses

208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License MD00049180 (WA) Primary
390200000X Student in an Organized Health Care Education/Training Program Student, Health Care · License 046085 (CT) Secondary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

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 Arthur Siek practice?
The practice location on file with NPPES is in Olympia, WA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Arthur Siek?
The National Provider Identifier (NPI) for Arthur Siek is 1326223801, 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 2008-03-11.