Skip to content
FonteumThe Graph
DataResearchCare CompareThe DifferAttestAPI
See the proof
  • Data
  • Research
  • Care Compare
  • The Differ
  • Attest
  • API
See the proof
Fonteum
Products
The DifferAttestAPIFHIR API
Data
Care CompareResearchData catalogSources
Company
AboutPressEditorial policyCorrections
Legal
Privacy policyTerms of serviceMedical disclaimer

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

© 2026 Fonteum, Inc. All rights reserved.

The U.S. healthcare graph AI can cite — every fact carries its source.

ARCHIVE

Snapshot Archive

Content-addressed snapshots of federal healthcare datasets. Each archive is SHA-256-attested, signed into an append-only chain, and independently re-derivable from its published manifest.

Source: Federal healthcare datasets·Snapshot: 2026-05-28·Method: 2026.05.28·ID: cms-nppes

Append-only chain

3Snapshots archivedContent-addressed records in the public archive.
1Links in chainSigned links from genesis to head.
23Federal source familiesDistinct upstream federal datasets.

CHAIN MANIFEST

/api/v1/chain

Head link 0.
8eb78f0071b9…
Open manifest

SIGNING KEY

Ed25519

fonteum-chain-2026-05-30.
ee:4b:9a:97:c6:04:1d:76
Published public key

GENESIS

Link 0

Signed 2026-05-30.
0000000000000000000000000000000000000000000000000000000000000000
Chain semantics

Browse the archive

Filter by dataset or capture window. Every row links to the full provenance record and a downloadable, content-addressed archive whose SHA-256 digest can be checked against the chain.

Archived snapshots with per-row SHA-256 provenance
CapturedDatasetRecordsSizeSHA-256 digestMethodSnapshot
2026-05-28
cms-nppes
—
1.03 GB
8b5267e250fd…
2026.05.28
Open
2026-02-01cms-nppes—1.03 GB8b5267e250fd…2026.05.28Open
2026-01-01cms-nppes—1.03 GB2625999a2b1b…2026.05.28Open
  1. [1]23 federal source families underlie the archived datasets; each snapshot records its upstream source and capture date.
  2. [2]Chain manifest — head pointer, total links, and published signing key.
  3. [3]Published Ed25519 signing key (JSON).
  4. [4]Chain semantics and offline re-derivation steps.