You bought something online, and your download included one or two extra files ending in
.attest or .private.attest. This page explains what they are.
Each file is a small, signed receipt from the store you bought from. It records what you bought, from whom, and — cryptographically signed by the seller — that the purchase is real. Think of it as a digital proof of purchase that lives on your own computer instead of only inside the store's database.
You don't need to trust this page, or the store, or take anyone's word for it. Anyone can verify the receipt directly — including you, right now, in your browser, with the file never leaving your machine.
*.private.attest, never send it to anyone.
That file is the proof that the purchase belongs to you. Anyone who has it can use it to claim they are the buyer. Sharing it — posting it, emailing it to "support", pasting it into a chat — hands your proof of ownership to whoever receives it. A real store or support agent will never need this file; they can already see your order. Keep it private, the same way you'd keep a receipt with your card number on it private.
That's the whole point of this format: the receipt still works. It doesn't call home, it doesn't need the store's servers to be running, and it doesn't expire when a shop closes down. A verifier can check it entirely offline, months or years later, using nothing but the file itself and the seller's published signing key. If a store you bought from shuts down, your receipt keeps proving what you own.