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Dr. Mark Gregory Ellis, MD

Pediatrics Physician in Eureka, CA · enumerated 2005.

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

National Provider Identifier

1003812744

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark Gregory Ellis
Credential MD
Sex Male
Practice address 2200 Tydd St, Eureka, CA, 95501
Phone (707) 269-7051
Fax (707) 269-7054
Enumeration date Jun 27, 2005
Last updated in NPPES Mar 17, 2018

Taxonomy & licenses

208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License G65432 (CA) Primary
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

What is the NPI number for Mark Ellis?
The National Provider Identifier (NPI) for Mark Ellis is 1003812744, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mark Ellis practice?
The practice location on file with NPPES is in Eureka, CA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-03-17.