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Mark C. Littlejohn, MD Pllc

Otolaryngology Physician in Frisco, TX · enumerated 2016 · authorized official Mark Littlejohn, Owner.

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

National Provider Identifier

1588020283

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Registry record

Entity type Organization (Type 2)
Legal business name Mark C. Littlejohn, MD Pllc
Practice address 8380 Warren Pkwy, Suite 504, Frisco, TX, 75034
Phone (972) 596-4005
Fax (972) 985-1253
Enumeration date Jan 11, 2016
Last updated in NPPES Jan 11, 2016

Taxonomy & classification

207Y00000X Otolaryngology Physician Allopathic & Osteopathic Physicians · License H5784 (TX) Primary

Authorized official

Name Mark Littlejohn
Title Owner
Phone (972) 596-4005

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 type of organization is Mark C. Littlejohn, MD Pllc?
Mark C. Littlejohn, MD Pllc is registered in NPPES as a Otolaryngology Physician (its primary provider taxonomy).
What is a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2016-01-11.