That&#x27;s not the same thing at all. Listing a $1999 product for only $19.99 is clearly a mistake, not intentional on the part of the seller, and it is obvious to any reasonable person that the buyer must know that this was a mistake when purchasing it.<p>On the other hand, listing a product for fair market value and then cancelling when the market value skyrockets after the sale is not at all reasonable behavior. I assume there&#x27;s some part of contract law that covers this sort of thing (since a sale is a form of contract).