An auction house must disclose the name of the seller -- in writing -- if it wants to collect on the sale when the purchaser refuses to pay up, a New York State appellate court has ruled. This comes upon the auction industry as a shock, given the universal practice that keeps the seller's identity confidential -- upon the seller's request.
http://art-unwashed.blogspot.com/2012/10/in-potentially-game-changing-decision.html