Well, in this case the order was &quot;confirmed&quot; then later StubHub claimed the tickets were &quot;listed in error&quot; which is an obvious lie. So for a start, they could start not obviously lying to their customers.<p>They could also add automatic sanity checking on listings, so sellers cannot accidentally list tickets at too low a price; and a manual offer acceptance stage in case the seller has chosen to list on multiple marketplaces.<p>They could also require that when a seller is selling a ticket, that the seller proves they actually have the ticket. If stubhub want to facilitate sellers engaging in speculation by selling tickets they don&#x27;t own, they could clearly mark such listings, with the seller placing a security deposit so their obligations can be met even if the market moves substantially against them.<p>In the event a seller works around these protections (such as by submitting fake proof they have the ticket, or refusing to meet their obligations if the market price of a ticket they shorted exceeds their deposit) stubhub could take care of forcing the seller to meet their obligations.