Shared auditors, social trust, and relationship-specific investment in the supply chain

An auditor common to a supplier and customer may serve an information role, reduce information asymmetry, or mitigate a potential hold-up problem in the supply chain. The information role of shared auditors could be more important in a lax institutional environment where a lack of trust exists between the supplier and customer. Using a sample of listed firms in China from 2009 to 2015, we find that (1) a shared auditor enhances the supplier’s relationship-specific investment (RSI), and (2) this positive association is stronger when the customer is located in a region with lower trust. We also document an incremental effect of a shared audit partner on enhancing the supplier’s RSI in addition to the effect of a shared auditor at the audit firm level. Additional analyses suggest that a shared auditor alleviates information asymmetry between the supplier and customer and hence improves the supplier’s RSI. A shared auditor particularly improves the supplier’s RSI when the customer is limited in its legal protection, which validates the usefulness of this unique research setting (China) for studying the information role of shared auditors. By extending the research on shared auditors and social trust, this paper provides a reference for companies that wish to explore the role of auditors in enhancing RSI in the supply chain.