An Upper Bound for the Firm's Cost of Employee Stock Options
给出了员工股票期权公司成本的一个上限，该上限取决于股票的风险收益和所有其他投资机会，但不依赖员工的风险偏好或财富，仅要求员工不对冲其期权。结果发现，使用期权定价模型可能高估成本，尤其对于高非系统风险的公司（如初创高科企业）。
This paper provides an upper bound to the firm's cost of employee stock options (ESOs). The upper bound depends on the risk and return of the underlying stock and on all other investment opportunities that are available, but it does not depend on employees' risk preferences or wealth. The only assumption that is required is that employees do not hedge their ESOs. One result of the model is that the overstatement from using options-pricing models for ESOs is likely to be greatest for firms with high unsystematic risk, such as small, high-tech firms in the start-up growth stages.