A costless contract agreeing to pay off the difference between a stock and some agreed future price lets both sides ride the risk inherent in owning stock without needing the capital to buy it outright.

• 入果一个低成本合同中达成协议付清股权和一些协议上的未来价格的差价，能让双方都以持有股权的形式而不用资本金将其彻底买入。