Shared evidence file
Ejemplo · Entrada de un piso de alquiler
The owner of this file has given you access to this page. It shows which exact files existed on which date and that they have not been modified since. Every check was repeated by the Sellat server when the page opened, and everything can be verified on your own without relying on Sellat.
The file existed on the date shown and has not been modified.
Each fingerprint is in a public Polygon transaction, checked just now against the network. Anchoring dates come from the network, not from Sellat.
Checked by the Sellat server on 09/30/2026, 11:51:51 PM UTC.
Files in this evidence file 1 file
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parquet-en-mal-estado.webp
Checked- SHA-256 fingerprint
-
27524c9669b7ee9773af7a95fdd3369a6708c861ef044d68430e81ae09fa8306 - Size
- 149 KB
- Received by Sellat
- 09/14/2026, 08:25:40 AM UTC Sellat server time; not the proven date
- Anchoring date
- 09/14/2026, 08:28:37 AM UTC
- Qualified seal date
- 09/14/2026, 08:25:47 AM UTC
Checks
- Polygon Anchored on Polygon Mainnet: block 93779656, 09/14/2026, 08:28:37 AM UTC polygonscan ↗ The file’s fingerprint (or the root of the batch containing it) was written into a transaction on a public network. Anyone can open it and read the block’s date.
- Merkle The fingerprint is included in the anchored batch Several files are anchored together in a batch. This check rebuilds the batch from the file’s fingerprint and confirms it reaches the root written to the network.
- Bitcoin Confirmed on Bitcoin: block 966942, as stated by the .ots file The same root was also recorded on Bitcoin through OpenTimestamps, a free, independent layer that confirms later.
- Qualified seal Qualified seal issued by FNMT-RCM: 09/14/2026, 08:25:47 AM UTC A qualified timestamp issued by FNMT-RCM, a qualified trust service provider under Regulation (EU) 910/2014. Sellat does not attest the time: FNMT-RCM does, and the seal is verified against the European Union trusted list.
Original file in custodyA copy the owner placed in custody. Before serving it, Sellat recomputes its fingerprint and only hands it over if it matches the proof. Check it yourself: download it and compute its SHA-256.
Two dates, each with its own source
The anchoring date is that of the public network block where the fingerprint was written; the network sets it. The qualified seal date is the one FNMT-RCM signed when the seal was issued, which may be later. They are always shown apart: the seal backdates nothing, and neither date is set by Sellat.
How to check it without Sellat
Nothing on this page requires trusting Sellat. With the evidence package and standard tools you can repeat every check on your own computer.
- Download the evidence package
Each file’s ZIP contains the fingerprint, the portable proof, the seal if there is one, the certificate of the authority that signed it, and a README with the exact commands.
- Compute the fingerprint of the exact file
If you have the file, compute its SHA-256 and compare it with the one on this page. A single different byte gives a different fingerprint.
shasum -a 256 file - Open the transaction on the public network
Each file’s link leads to a Polygon explorer. The transaction’s data field holds the fingerprint or the batch root, and the block has its date.
- Verify the qualified seal
The seal (.tsr) is checked with OpenSSL against the authority certificate (.pem) in the package, and that certificate against the EU trusted list.
openssl ts -verify -digest <fingerprint> -in seal.tsr -CAfile autoridad-sellado.pem -partial_chain
The full commands are in the package README.
What it proves and what it does not
The package proves that this exact file existed on that date and has not been modified. It does not prove who created it, who took the photo, or what happened in front of the camera.
The seal is signed by FNMT-RCM, not by Sellat.
Sellat is not the party attesting the time. The qualified seal is issued by a qualified timestamping authority of the FNMT-RCM, and its signing certificate travels inside your package. We are the intermediary that joins your fingerprint to that seal and hands it to you in a tidy folder.
This proof was created with Sellat. Verify it yourself · Create your own