Quasi Rents to Audit Firms from Longer Tenure
SYNOPSIS We offer an economic explanation for why audit firms oppose mandatory firm rotation. Using an innovative sample that overcomes sample selection biases, we find that fees for Big 4 audit firms increase noticeably over the audit firm's tenure. In contrast, fees for non-Big 4 audit firms decline as tenure lengthens. Using audit report lag as a proxy for audit cost, we find that audit cost declines over the audit firm's tenure, and this decline is even larger for Big 4 auditors. Our results indicate that Big 4 engagements become more profitable or earn “quasi rents” over time, which may explain why Big 4 audit firms are so opposed to firm- but not partner-rotation. Whether non-Big 4 auditors earn any quasi rents remains doubtful. Our findings suggest a need to better monitor auditor independence and audit judgments when tenure is long, especially for Big 4 auditors, because economic bonding between the audit firm and client tends to increase over time. JEL Classifications: M40; M42.