Code of ethics 9 states
"To furnish requested advice to the best of my ability and knowledge, and not to take advantage of superior knowledge on my part to the disadvantage of a less knowledgeable collector."

So surely if the seller refuses to disclose, or, as is more often the case, makes buyers believe there are less than there actually are (which has the sole effect of inflating the value), then that qualifies as 'superior knowledge'.

That is what I think? What do you think? I would have thought that as a long time President you would have had a clear view on this

David; As a "long time President (1988-1999) I DO have a clear view on this issue and I think I know where you are not-so-subtly trying to go with this thread. If a club member feels that he has been cheated or otherwise has been harmed, he/she has recourse by submitting a claim with the club's claim director. Having said that; if in jest someone hypothecially posted on TCB several years ago "Does Macy's tell Gimble's" does not constitute a violation of the club's COE ... Do you really want to go there David?