I say, and with God's success: Its meaning is that the seller enters into a contract to sell shares of a certain company at a later date, and it is known that adding a sale for the future is not valid; because it is not permissible to add ownership for the future, and because it is a sale of a debt for a debt, which is prohibited. Moreover, in most of these contracts, the item being sold is not owned by the seller at the time of the contract, and in most cases, this sale does not intend to deliver the sold item and receive it, but rather the contract ends with the settlement of price differences, which is a type of speculation and gambling based on estimation far from actual trades, and it contains countless harms to the economic system, as our Sheikh mentioned in the jurisprudence of sales (1: 370-371), and God knows best.