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Dr. Leonard Mason, MD

Surgery Physician in Newark, DE · enumerated 2007.

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

National Provider Identifier

1114122355

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Registry record

Entity type Individual (Type 1)
Name Dr. Leonard Mason
Credential MD
Sex Male
Practice address 4735 Ogletown Stanton Rd Ste 3301, Newark, DE, 19713
Phone (302) 623-4370
Enumeration date Jun 18, 2007
Last updated in NPPES Aug 13, 2020

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License MD457506 (PA) Secondary
2086S0127X Trauma Surgery Physician Allopathic & Osteopathic Physicians · License 53123 (TN) Secondary
208600000X Surgery Physician Allopathic & Osteopathic Physicians · License C1-0013726 (DE) 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

Is NPI 1114122355 active?
Yes, as of the latest NPPES snapshot, NPI 1114122355 is active (record last updated 2020-08-13).
How do I verify Leonard Mason's NPI record?
Cross-check NPI 1114122355 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-08-13.