NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Mark B Layman, M.D.

Internal Medicine Physician in Seminole, TX · enumerated 2005.

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

National Provider Identifier

1790789303

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Registry record

Entity type Individual (Type 1)
Name Mark B Layman
Credential M.D.
Sex Male
Practice address Seminole, TX, 79360
Phone (432) 758-6363
Fax (432) 758-6550
Enumeration date Jun 10, 2005
Last updated in NPPES Jun 28, 2010

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License K9104 (TX) 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
096903202 Medicaid TX -
0047DY Other TX BCBS OF TEXAS
121479 Other TX CHIPS NUMBER
117485100 Other TX FIRSTCARE ID

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.

Read the full guide → Validate an NPI →

Frequently asked questions

Where does Mark Layman practice?
The practice location on file with NPPES is in Seminole, TX. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mark Layman?
The National Provider Identifier (NPI) for Mark Layman is 1790789303, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2010-06-28.