Does audit firm tenure enhance firm value? Closing the expectation gap through corporate social responsibility

Purpose - This study aims to examine the moderating effect of audit firm tenure on the association between corporate social responsibility (CSR) and firm value. Prior studies provide mixed results on this association, which may be due to differing theoretical expectations related to CSR and firm value. It is also possible that external stakeholders are unable to differentiate between positive and negative CSR investments, as CSR reports are generally not assured by independent third parties. Thus, the authors propose that audit firm tenure may be used by external stakeholders to evaluate CSR performance. Design/methodology/approach - The authors use an ordinary least squares regression to examine the moderating effect of audit firm tenure on the relation between CSR and firm value after controlling for other determinants of firm value and various internal and external governance mechanisms documented in the literature. The sample consists of 15,707 firm-year observations from US firms during the sample period of 2000 to 2012. The authors measure CSR quality using rating scores from MSCI ESG STATS (formerly the KLD database), audit firm tenure as the number of years the incumbent auditor has served the client and firm value using Tobin’s Q. Findings - The results indicate that CSR is positively associated with firm value when audit firm tenure is long but not when tenure is short. The results are robust to alternative measures of firm value, CSR performance scores, and individual CSR dimensions. The evidence supports the argument against mandatory audit firm rotation in the USA. Research limitations/implications - Future studies could examine a similar issue in alternative settings and/or look at cross-sectional variations among firms on the association between CSR and firm value by other auditor traits such as auditor industry specialization and big-name reputation. Additionally, as auditor alone is unable to ensure the quality of management disclosures and their accountability, future studies could examine the moderating effect of internal and other external governance mechanisms on the association between CSR and firm value, exploring when the signaling effect of auditor tenure on CSR reporting quality and its effect on firm value is most salient. Practical implications - The findings are important to regulators and investors. The authors provide evidence that longer audit tenure serves as a signaling device for external investors with regard to the quality of a firm’s CSR performance. Hence, the study facilitates regulators’ cost-benefit analysis related to mandating audit firm rotation. The evidence suggests that mandating a term limit on auditor tenure may have the unintended consequence of eliminating a signaling effect of auditor tenure on the quality of CSR disclosures under information asymmetry. This supports the Public Company Oversight Board’s decision to forgo the requirement of mandatory audit firm rotation in the USA. Originality/value - Prior literature presents mixed findings on the association between CSR performance and firm value based on a variety of underlying theories (economic, stakeholder and contingency theory). Literature on mandatory auditor rotation has concentrated on the auditor tenure effect on perceived and actual audit quality as reflected in earnings quality. Relying on agency theory, this study posits that auditor tenure serves as a signal for the quality of CSR activities in the absence of CSR assurance reporting as CSR quality can be difficult to evaluate. The authors provide evidence that audit tenure moderates the association between CSR activities and firm value and longer audit tenure makes it more likely that the CSR activities are associated with increased firm value.