Dealers and if they dont buy the watch there is lots of ways that they get details. They take action against the AD for not selling to the right client...in the UK this resulted in 6 months suspension of deliveries for one and loss of agency f it happens again!! Sometimes its not the dealers fault...there was a Tiffany 5711 that went up for auction recently and this was from a very good Customer of theirs that had spent $ 400 000 just that year!! I dont believe he is that lucky to get a T stamp again!!