Apparently, a private collector has the following Top Of The Pops shows, that the BBC have destroyed their copies of
08/09/77 (latest "missing" complete edition)
04/10/73 (500th Show)
+ various "missing" 60's editions not listed.
This collection is for sale, however the BBC are not prepared to pay to recover these "missing" gems, as they expect the copy holder to hand over their footage for free and the copy returned after the BBC has made a copy.
What do you think, should the BBC expect the copies to be handed over? They do own the copyright, but they deliberately destroyed the copies they had many years ago. It's an interesting debate