Evidence Anchors
Every hour The NFC Mint validation service anchors its evidence log. That hour's scans, notes, and records become the leaves of Merkle trees, the roots are chained to the previous anchor, folded with the latest NIST Randomness Beacon pulse and drand quicknet round, and stamped by an RFC 3161 timestamp authority. Once a day the newest anchor, the tip, is stamped a second time and submitted to OpenTimestamps for a Bitcoin attestation. This page publishes each day's tip with its stamps. It carries hashes and attestations only, never scan contents, leaf keys, or tag data.
The open day is published as it grows in today.json. The newest closed day is also available as latest.json together with the verification constants.
Daily Tips
This page is rebuilt after every hourly run, so a Bitcoin block that confirms later fills in within the hour.
| Day | Tip Hash | Timestamp Authority | Bitcoin Block | drand Round | Files |
|---|---|---|---|---|---|
| 2026-10-20Anchor #1967 | 99d7a44e53dc5a74c93ee42755dd39e088c024bc7f6b09cf857aefda2a7ed873 | freetsa.org2026-10-20T00:14:11.000Z | Pending | 33217295 | Record Request Response Bitcoin Proof |
| 2026-10-19Anchor #1943 | b1819ef5c1d900269405970fb6f4f938ad2c1187ee8ffac92ee54429d93fd55b | freetsa.org2026-10-19T00:14:48.000Z | Block 9720812026-10-19T00:44:27.000Z | 33188507 | Record Request Response Bitcoin Proof |
| 2026-10-18Anchor #1919 | 6d920d5eb8b49e9f66e5fe7c9eaf938da7090b2d9564118fc4f8cb8e99733d86 | freetsa.org2026-10-18T00:14:26.000Z | Block 9719222026-10-18T00:27:47.000Z | 33159700 | Record Request Response Bitcoin Proof |
| 2026-10-17Anchor #1895 | 6e739002673819ed8f2d831dbd11020518dc83924d2fb188331e623ea0c7d179 | freetsa.org2026-10-17T00:14:43.000Z | Block 9717852026-10-17T00:52:05.000Z | 33130905 | Record Request Response Bitcoin Proof |
| 2026-10-16Anchor #1871 | 192cb38c5b7da39ae8b39a64c59695d2804d81aaaf8d1f00583091186fdcf029 | freetsa.org2026-10-16T00:14:13.000Z | Block 9716382026-10-16T00:21:10.000Z | 33102095 | Record Request Response Bitcoin Proof |
| 2026-10-15Anchor #1847 | b5ce390f34d0d31ef182d8ca9a124ffa382838c97a93494dbff2b420a306c9c6 | freetsa.org2026-10-15T00:14:55.000Z | Block 9714842026-10-15T00:32:09.000Z | 33073309 | Record Request Response Bitcoin Proof |
| 2026-10-14Anchor #1823 | d8af368b8112a5fece6f8a3bbb8b63cdbb519d989eddc6d0fc7dd39625ef41dc | freetsa.org2026-10-14T00:14:46.000Z | Block 9713252026-10-14T00:26:49.000Z | 33044506 | Record Request Response Bitcoin Proof |
| 2026-10-13Anchor #1799 | 7798a26c3ef54124c69534bcbd4eb95637bc093c633fcb59788a19bbb2a3846e | freetsa.org2026-10-13T00:14:50.000Z | Block 9711622026-10-13T00:26:36.000Z | 33015708 | Record Request Response Bitcoin Proof |
| 2026-10-12Anchor #1775 | 8ecf5bdc83290fe718fb35e6e01b3ed54de42680445abc748ba3f6c53f0cd23b | freetsa.org2026-10-12T00:14:46.000Z | Block 9710102026-10-12T00:20:26.000Z | 32986906 | Record Request Response Bitcoin Proof |
| 2026-10-11Anchor #1751 | 0dd6e84a23158787e210d4a943d237dfb98d8936bbdcb47d9dc9625b4891a8b7 | freetsa.org2026-10-11T00:14:32.000Z | Block 9708512026-10-11T00:27:25.000Z | 32958102 | Record Request Response Bitcoin Proof |
| 2026-10-10Anchor #1727 | 815460fab6ac9a7b01c5d5006ef4ecf33acb7a814e46b088d339eaa64c36b6cc | freetsa.org2026-10-10T00:14:48.000Z | Block 9706982026-10-10T00:44:55.000Z | 32929307 | Record Request Response Bitcoin Proof |
| 2026-10-09Anchor #1703 | 7289556eb38c3127714bcd7286d24545f0af058abb70be012834b91aceb6d1ed | freetsa.org2026-10-09T00:14:31.000Z | Block 9705532026-10-09T00:20:31.000Z | 32900501 | Record Request Response Bitcoin Proof |
| 2026-10-08Anchor #1679 | d9059321f86557a71c762e69e600d3df5feccbce39683dc47e929b1ee39646ac | freetsa.org2026-10-08T00:14:58.000Z | Block 9704122026-10-08T00:29:42.000Z | 32871710 | Record Request Response Bitcoin Proof |
| 2026-10-07Anchor #1655 | ea51d1d57ce97609afbb70ae21e831275b77f661567a9a63a0f3f2bb34c7f538 | freetsa.org2026-10-07T00:14:05.000Z | Block 9702582026-10-07T00:16:48.000Z | 32842893 | Record Request Response Bitcoin Proof |
| 2026-10-06Anchor #1631 | b62e4f37f55324c61dff7c92aca607b475cd90be472a46414af7765ccc562393 | freetsa.org2026-10-06T00:14:14.000Z | Block 9701032026-10-06T00:24:04.000Z | 32814096 | Record Request Response Bitcoin Proof |
| 2026-10-05Anchor #1607 | 3f9616ab50888307534adff1eaaab9ae007ddd9b28545ee3d90f2d1a06c4791a | freetsa.org2026-10-05T00:14:47.000Z | Block 9699252026-10-05T00:31:08.000Z | 32785307 | Record Request Response Bitcoin Proof |
| 2026-10-04Anchor #1583 | acfccfe3fc64171aff903a6f03544b69820c0e7b02e7bc9261abacc1057cfac8 | freetsa.org2026-10-04T00:14:59.000Z | Block 9697832026-10-04T00:36:22.000Z | 32756511 | Record Request Response Bitcoin Proof |
| 2026-10-03Anchor #1559 | f4a19863bae4e027c753ad80a52f6be5e0098bd245b9069ad46f1b6921358ba8 | freetsa.org2026-10-03T00:14:22.000Z | Block 9696502026-10-03T00:20:10.000Z | 32727698 | Record Request Response Bitcoin Proof |
| 2026-10-02Anchor #1535 | 19c24bb6392ed4b5d89f465d4fe6fed388755400e847c2298bee0d0a26722f23 | freetsa.org2026-10-02T00:14:56.000Z | Block 9695082026-10-02T00:31:40.000Z | 32698910 | Record Request Response Bitcoin Proof |
| 2026-10-01Anchor #1511 | 9752a4cd519b31d1966e648415df17d0101cc874abeb8ddf88420535acd0273d | freetsa.org2026-10-01T00:14:57.000Z | Block 9693732026-10-01T00:57:44.000Z | 32670110 | Record Request Response Bitcoin Proof |
| 2026-09-30Anchor #1487 | faec1a3b8499c88445c3f6e2c1a55a876334e7932db3eca1469a52f2fab8414b | freetsa.org2026-09-30T00:14:57.000Z | Block 9692302026-09-30T00:22:29.000Z | 32641310 | Record Request Response Bitcoin Proof |
| 2026-09-29Anchor #1463 | a988fa26c214a9e20e2589cab41071761a75034c7c9ddd343201cf3a47b6a606 | freetsa.org2026-09-29T00:14:28.000Z | Block 9690722026-09-29T00:24:20.000Z | None | Record Request Response Bitcoin Proof |
| 2026-09-28Anchor #1439 | 634b41be8b5d342b9c950b5c405223aa1a553c37655251f5c20053888c57a8e2 | freetsa.org2026-09-28T00:14:53.000Z | Block 9689082026-09-28T00:35:36.000Z | None | Record Request Response Bitcoin Proof |
| 2026-09-27Anchor #1426 | 9379486388267cbd69ed8a58309defebc82f36ee7064275482bccdd6816620c1 | freetsa.org2026-09-27T11:14:04.000Z | Block 9688342026-09-27T11:17:54.000Z | None | Record Request Response Bitcoin Proof |
Verify a Day
To check a day yourself, save its request, response, and record files. Once the files are saved, nothing in this check needs our server. The commands below use the newest day.
Use openssl to confirm that the response answers that request, that the request's message imprint equals the tip hash printed here, and that the signer chains to the authority's published root.
openssl ts -verify -in 2026-10-20.tsr -queryfile 2026-10-20.tsq -CAfile freetsa.pem openssl ts -reply -in 2026-10-20.tsr -text
Then give the tip hash and the Bitcoin proof file to the OpenTimestamps client, which walks the proof to a Bitcoin block header.
ots verify -d 99d7a44e53dc5a74c93ee42755dd39e088c024bc7f6b09cf857aefda2a7ed873 2026-10-20.ots
The record lists every hourly anchor of that day, so you can recompute each anchor hash from the recipe below, confirm that each one chains to the next, and confirm that the anchor the daily stamp names is among them. Each drand round verifies against the pinned quicknet public key below.
Anchor Hash Recipe (Version 2)
anchor_hash is SHA-256 over the UTF-8 bytes of these newline-joined parts in order, the literal evidence-anchor-v2, the previous anchor hash in hex or empty, the NIST pulse URI or empty, the NIST pulse output in hex or empty, the drand chain hash, the drand round number, and the drand signature in hex (all three present only when the signature verified, otherwise all empty), and one part per table in the order validations, scan_annotations, tamper_tag_meta, oncemark_tag_meta, each written as table:from-to:count:root with the window bounds, the leaf count, and the RFC 6962 Merkle root in hex.
Constants
- drand Chain Hash
- 52db9ba70e0cc0f6eaf7803dd07447a1f5477735fd3f661792ba94600c84e971
- drand Public Key
- 83cf0f2896adee7eb8b5f01fcad3912212c437e0073e911fb90022d3e760183c8c4b450b6a0a6c3ac6a5776a2d1064510d1fec758c921cc22b0e17e63aaf4bcb5ed66304de9cf809bd274ca73bab4af5a6e9c76a4bc09e76eae8991ef5ece45a
- drand Genesis Time
- 1692803367
- drand Period
- 3
- drand Scheme
- bls-unchained-g1-rfc9380
Timestamp Authority Trust Bundles
- timestamp.digicert.com
- https://cacerts.digicert.com/DigiCertTrustedRootG4.crt.pem
- timestamp.sectigo.com
- http://crt.sectigo.com/USERTrustRSACertificationAuthority.crt
- freetsa.org
- https://freetsa.org/files/cacert.pem
Mirror
Anchor hashes are also mirrored write-once to a separate provider (Cloudflare) at https://anchor-heartbeat.nfcmint.workers.dev. Compare the mirror's records with this page; the two must agree.
Published 2026-10-20T00:14:14.035Z