Effects of Multiple Clients on the Reliability of Audit Reports
发现审计师同时服务多个客户会产生两种外部性：一是客户股价受其他客户审计意见影响，二是审计师财富有限时增加客户会降低审计质量、提高审计失败概率，且加强监管可能适得其反。
This paper demonstrates the existence of two different kinds of externalities induced by an auditor servicing multiple clients at the same time. First, we show that the capital market price for a client can increase in the number of qualified reports that his auditor issues to his other clients, thus producing a stock price externality. Second, when the audit firm has limited wealth, an additional client can actually decrease the audit quality and increase the average likelihood of audit failure relative to a single‐client setting because of reporting externalities. Our analysis also demonstrates how requiring a more effective audit oversight mechanism can actually produce unintended consequences such as an increased likelihood of audit failures.