Estimating the Compliance Costs of Securities Regulation: A Bunching Analysis of Sarbanes-Oxley Section 404(b)

An extensive literature has analyzed the Sarbanes-Oxley (SOX) legislation enacted in 2002, but its social welfare consequences remain controversial. One of the most significant provisions of SOX – auditor attestation of internal controls under Section 404(b) – has been applied only to firms that have a public float (i.e. the market value of shares held by non-insiders) of at least $75 million. Public float is not reported in standard databases; this paper “scrapes” public float data from 10-K filings, resulting in about 161,000 observations at the firm-year level for the universe of reporting entities for fiscal years 1993-2015. The analysis compares the number of public float observations immediately below the $75 million threshold to a smooth counterfactual density estimated using a flexible polynomial fitted to the observed density away from the threshold. In the pre-SOX period, there is no detectable divergence between the actual and counterfactual density around $75 million. Since the enactment of SOX, there is substantial and statistically significant “bunching” below the threshold, exhibiting a bimodal pattern. The magnitude of bunching implies that firms around the threshold reduce their public float by about $1.7 million. This estimate is consistent with SOX 404(b) imposing a net compliance cost of about $4-$6 million (in present value terms) on firms in the region of the threshold. The results are robust to considering various alternative explanations for bunching, including the possibility that firms’ insiders avoid crossing the threshold in order to continue extracting private benefits of control. The paper also explores potential financial and economic consequences of bunching, in particular on the debt financing and investment choices of firms close to threshold.