Give a page address, or paste the text of a work. The answer says whether a registered record exists for that exact text, who claimed it, and when. Nothing you check here is stored or added to the register.
Or paste the text of the work. The body only, without the title: the record covers the text of the work, and the title lives beside it.
Some pages only show their content to signed-in readers, and Alltio does not sign in. If a page cannot be read from here, open it yourself and paste the text; the answer is the same. Every answer is signed by the registry and can be verified against the published keys; the Lookup API gives the same answers to machines, in batches.
Checking your own work? Sign in and use Is this mine: it compares a page against your own registered text and can see partial and edited copies, which a yes-or-no check cannot.