I don't this concerns just bootlegs as i recall seeing this before on the page of an official release. I guess a label/artist can block a release from the marketplace if he/she really wants to?
this would be interessting to know, an user wrote under the "TTJ" Label site:
Sooo glad to have secured all these gems into my collection. I suppose these are not sanctioned by TT, but the man has had little time to arrange reissues of his genius work, so I guess somebody else did. These series of unofficial pressings include many tracks which are officially unissued, and maybe never will be.
which would mean somebody can tell discogs and they check it?
... thank you for listening !