The Land Registry is only a record of ownership and is always searched as part of the conveyancing process however you still need the actual Deeds to be transfered either between mortgagors or banks when you sell, so most people should be safe! It is possible to get quite far down the line though without the Deeds, and if there is a sloppy solicitor then I suppose it can all go very pear shaped. Deeds can also be falsified in cases of elaborate fraud.