[ValueAddedRS]

I'm assuming you're talking about situations where someone lists an item they don't have on eBay, then have it "drop shipped" from another seller on Amazon once it sells (or vice versa)?

If so, you might be interested to know the INFORM act requires sellers who meet the $20K threshold to disclose if a different seller is shipping the item and if so, if the buyer request, they have to provide the contact info for that seller.

"Whether the high-volume third party seller used a different seller to supply the consumer product to the consumer upon purchase, and, upon the request of an authenticated purchaser, the information described in clause (i) relating to any such seller that supplied the consumer product to the purchaser, if such seller is different than the high-volume third party seller listed on the product listing prior to purchase."

I know a lot of buyers have been frustrated with this kind of online arbitrage drop shipping for years and most of the marketplaces don't enforce their policies about it - it will be interesting to see if this helps curb the practice.