A corporation is an entity that could be sued or could lose more money than it's worth, but the value of a corporation can never fall below zero to the investors because the investors are not liable for the mistakes of the corporation.

公司是一个实体,它可能被起诉,或者亏损额超过了自身的价值,但是对于投资者而言,公司的价值永远不会小于零,因为投资者对公司的过失,不负有责任

耶鲁公开课 - 金融市场课程节选

You work for XYZ Corporation; the share is trading at $10 a share; they would give you "At the money" Or "Out of the money" Options -say options to buy the stock at $11 a share.

你在XYZ公司工作,当前股票价格是每股十美元,他们会给你,平价期权或者价外期权,比如以每股十一美元来购买该股票的期权

耶鲁公开课 - 金融市场课程节选