Nice work from BiffyRich;

http://www.manxgeocaching.com/index.php?showtopic=82

I had permission from them a couple of years ago for a cache in the Ballaugh Curraghs, but (as so often happens in these things), by the time BiffyRich applied they were no longer aware of the permission they'd granted (luckily, I'd kept the e-mails).
Now they seem to have formalised a procedure, and this is outlined in the posting I've linked to.