Paul McCartney has delved back into the realm of Beatles myth by announcing that Carnival Of Light, the band's lost 14-minute experimental track, is likely to be released into the public domain.
We'll have to wait for the full interview, of course, but Paul says nothing about "releasing it into the public domain" in the BBC clip Bobber posted. It's probably just journalistic sloppiness, the writer using "public domain" to mean "make available to the public" and being either unaware or uninterested that it also means "unprotected by copyright." And where does he get "likely to be released" from?
As for the clip itself, Paul doesn't sound like he's grinding an axe: it's the interviewer who brings up "Carnival Of Light" and Paul offers a straightforward description of it and how it came about. It's only an excerpt, though. As well, he says that "Carnival" "came to light" during the tape review for
Anthology, which perhaps implies that he did indeed forget all about until he heard it again in the nineties.