There is one prior study on the consequences of allowing audit firms to become LLPs. Muzatko et al. (2004) examine how
LLP adoption affects the magnitude of under-pricing in the initial public offerings of US companies. In their study, the treatment
variable for LLP adoption is a dummy variable equal to one in 1994 (the adoption year for every audit firm in their sample) and
zero in 1993 (the pre-adoption year for every firm). Because every audit firm in their sample becomes an LLP in 1994, they lack
a control sample of audit firms that do not become LLPs. Unlike Muzatko et al. (2004), our sample comprises audit firms that
become LLPs and audit firms that retain unlimited liability. This allows us to investigate the consequences of LLP adoption
using a difference-in-differences research design that controls for audit firm fixed effects and year fixed effects. In addition, it
allows us to examine why some audit firms change their organizational form whereas other firms do not. We show that larger
audit firms and firms that have riskier clients are more likely to become LLPs. In contrast, the smaller audit firms and firms with
less risky clients remain as unlimited liability partnerships. In addition, our study examines whether the LLP structure affects
audit quality, audit pricing, and audit firms’ client portfolios, whereas Muzatko et al. (2004) examine only IPO under-pricing.