Are NPI numbers public?

Yes. NPI numbers are public federal identifiers in CMS NPPES. This page shows the public NPPES facts Fonteum has for NPI 1861432973: provider name, entity type, taxonomy, practice location, enumeration date, last-updated date, and source snapshot date. It does not include patient information.

What does the NPI record show for Mark Johnson?

Mark Johnson (NPI 1861432973) appears in CMS NPPES as ophthalmologist in Sun City West, AZ. NPPES is administrative identity data submitted to CMS by providers and organizations; this page displays the source snapshot date as 2026-05-06.

Does this page assign a provider score?

No derived score is assigned on this provider page. NPPES is an identity registry; when a CMS QPP MIPS value is available, Fonteum displays that public CMS value with its source, and absence of a MIPS value is not a quality signal.

Does no exclusion match amount to a clearance?

Coverage is indeterminate, so this page makes no negative exclusion determination. This is not a clearance; check the current issuing-agency lists.

Where does the provider data come from?

The identity fields come from CMS NPPES. Additional sections appear only when a public source has a matching row, such as CMS PECOS, CMS Open Payments, Medicare Part D, CMS QPP MIPS, OIG LEIE, or state Medicaid exclusion lists. Source and date metadata appears where the response supplies it; unavailable dates are labeled.

Mark Johnson — NPI 1861432973: exclusion status

Name: Provider record — NPI 1861432973 (Mark Johnson)
Creator: Fonteum
License: https://www.usa.gov/government-works

Built on the authoritative federal record

The primary sources, named on every page.

These are the federal agencies whose public datasets Fonteum ingests and attributes — the issuing authorities, not customers or partners. Every figure on the site links back to one of them.

CMS
HHS-OIG
HRSA
FDA
NLM
NUCC
Census
BLS
BEA

See the full source registry, with license and refresh cadence for each →

Reproducible by design

Published figures name their source and date.

Source and date

Published research identifies its government file and observation date. Source-file SHA-256 coverage is disclosed separately; facts do not currently link deterministically to signatures.

Reproducible SQL

Each study ships the exact query behind its figures, run against the same dated copy of the federal file we used. Re-run it yourself.

Daily observations

The platform records table row counts daily. Those observations detect local drift; they do not imply that an upstream publisher released or Fonteum ingested new data that day.

Named medical review

Reviewed by Jennifer Montecillo, MD, medical reviewer. Non-practicing medical reviewer.

Read the full provenance and attestation methodology →

Request access

Mark Johnson — NPI 1861432973: exclusion status — Fonteum

Cross-source identity

Sources that publish this NPI

National Provider Identifier 1861432973 appears in the source rows shown below. Sources that do not publish NPI use their own identifiers and are not treated as deterministic NPI matches. Chips show response-supplied dates when available; otherwise they are labeled date unavailable.

NPPES

Federal sources carrying NPI 1861432973
Federal source	Key	What it provides	Source & date
CMS NPPES	NPI 1861432973	Registry identity — ophthalmologist, taxonomy 207W00000X	Source:CMS NPPESSnapshot 2026-05-06

Mark Johnson

Public NPPES answers

Are NPI numbers public?

What does the NPI record show for Mark Johnson?

Does this page assign a provider score?

Does no exclusion match amount to a clearance?

Where does the provider data come from?

Sources that publish this NPI

MIPS quality score

Standing

Who owns, operates, or is affiliated with this provider

Retained versions for this record

Mark Johnson

Public NPPES answers

Are NPI numbers public?

What does the NPI record show for Mark Johnson?

Data-use and correction resources.

Does this page assign a provider score?

Does no exclusion match amount to a clearance?

Where does the provider data come from?

Sources that publish this NPI

MIPS quality score

Standing

Who owns, operates, or is affiliated with this provider

Retained versions for this record

Context for this record