Yo don't need regulation, you need informed buyers, if they know the market value of things they can't get scammed, thats one of the benefits of an auction house and that's the reason prices in warframe market are half or less of what people ask in trade chat. An auction house would fix all the current problems with trading, because it's the closest you can get to a perfect competition market, but since it would cause deflation it goes against DE interests. If people aren't getting scammed it means prices are lower, which means people need less platinum, which means they buy less platinum from DE and they make less money. That's the sole reason why we don't have an auction house yet, you getting scammed makes DE earn more money.