Registering is easy.
Declaring well is what gives it weight.
Uploading a file and getting a seal takes a minute. The part almost nobody fills in — the extended declaration — is what separates a certificate that proves a date from one that supports a claim.
One thing before you start
The registration form itself is currently served in Spanish. This guide explains exactly what each field is so you can fill it in with confidence, and the option labels below are the official English ones from the same catalogue the form uses. The proof produced — a SHA-256 fingerprint, an RFC 3161 seal and a Bitcoin anchor — is language-neutral.
Pick the original file
Not a forwarded copy — the fingerprint is computed over the exact bytes you hand over.
SHA-256 runs on the bytes you upload. Send the version that went through a messaging app and you have sealed the recompressed copy, not your original — and your original will no longer match the certificate.
Take it from the camera, the export folder or the project. That is the one that counts.
No account, no card. The email field is optional and you never have to confirm it.
Give it a title that still makes sense in a year
It goes on the certificate and on the public verification page.
No format rules, but a title carrying the what and the when finds itself later. "IMG_4821" does not.
Write it for the stranger who will read it during a dispute, not for your own folder.
Open the extended declaration. This is where the value is.
It is optional and it starts collapsed — which is exactly why almost nobody fills it in.
Nothing inside is required, and that is the problem: it is one click to skip, the certificate comes out anyway, and it says far less.
An undeclared certificate proves a file existed on a date. A declared one also records what it is, why you were entitled to register it, and what you allow others to do. The first wins an argument about dates; the second supports a claim.
Measured on this platform: of the works registered through the public route, only a handful declared a basis of rights. Not because people did not want to — because nothing told them which option to pick.
For code only, after choosing the software category: MIT · Apache-2.0 · GPL-3.0-only · GPL-3.0-or-later · AGPL-3.0-only
Category — what the work is
It changes how the file is handled, not just how it is labelled.
For the text categories — lyrics, article, script, software, invention, web capture — the full text is deposited INSIDE the certificate from page 2, with a per-page hash chain so no page can be swapped.
Choosing "software or code" adds MIT, Apache, GPL and AGPL to the licence list. They do not appear for a photograph, because offering GPL for a photo would be misleading.
Two carry warnings worth reading: "invention" is NOT a patent application, and "trademark" is NOT a trademark registration.
Basis of rights — why you may register it
This is the question you will be asked if anyone contests the registration.
Each option prints a different clause on the certificate, written in the first person. You are not filling a dropdown; you are signing a statement.
Several ask you to keep supporting paperwork — a commissioning contract, an assignment, an agency licence reference, the creator’s authorisation. The certificate does not store it for you.
If you made it, it is "own work" and there is nothing to weigh up. If you are torn between two, the honest one is the one you could back with a document.
Licence — what you allow others to do
Registering publishes nothing and grants nothing on its own.
The licence is what YOU authorise, dated and sealed like everything else.
If you want to authorise nothing, "all rights reserved" says so explicitly — which is different from leaving it blank and forcing the reader to guess.
Careful with CC0: it places the work in the public domain and is IRREVOCABLE. The form warns you before you confirm. It is not a reversible "free".
Identification — optional, and the one that weighs most
It never appears on the public verification page.
An anonymous certificate proves a file existed. One with a declared identity also proves who declared it — which is precisely what is in dispute when two people claim the same work.
It is the field most people skip and the one most people wish they had filled in.
Accept the lawfulness declaration and submit
That checkbox is the only mandatory one; the IP consent is separate and unticked.
The lawfulness and authenticity declaration is required: it is what moves responsibility for what you declared onto you.
Consent to record your origin IP sits apart and starts UNTICKED. A pre-ticked consent is not consent, which is why it is not bundled with the legal acceptance.
From here the system works: fingerprint, quarantine, RFC 3161 seal, signature and Bitcoin anchor.
If an AI agent does it for you
The MCP server exposes a guia_de_declaracion tool that hands the agent these same options with the same decision rules, generated from the same catalogue as this page.
What an agent does not do is sign for you. The basis of rights and the licence are first-person statements of responsibility, and the tool is written so the model asks you rather than filling them in on its own. Sealing over MCP creates a draft you approve: no AI certifies anything without a person confirming it.
Now with your own work
Free, no account, no card. If something does not fit, leave it blank: declaring too little is recoverable, declaring wrongly is not.