Because this is an RFP, the auction format will follow a reverse Dutch auction, the beginning price is low, and gradually increase over the course of the auction. If Bob wants a piggy that he can not find on the market, he can request one, and see if anyone will fulfill the request. Bob then puts this RFP up for auction, in doing so sends along the reserve amount of USDC in the transaction. Here Native Purchase refers to the idea that someone needs to purchase this RFP, thereby collateralizing it, so that it is useful to Bob. Alice, our liquidity provider, decides that she will fulfill Bob's request, and purchases this RFP.