Ripple effects: Sarbanes Oxley's impact upon investor risk in a global economy

Abstract

Purpose

This study seeks to evaluate, in a global context, the impact of Sarbanes Oxley Act on a particular risk measure of importance to investors (risk‐adjusted returns), and two measures of risk due to asymmetry (upside and downside risk). A unique dataset permits a dual evaluation of the law's impact on such measures in leading non‐US economies as well (i.e. “ripple effects”).

Design/methodology/approach

Hypotheses are empirically evaluated on a sample (n=712) of the largest US and European firms (control) using daily return data from 1993 through 2009 – one of the most extensive data sets employed in the literature on this topic to date. The reliability of the risk measures is carefully evaluated using multiple approaches, including Fama‐MacBeth regressions. A series of difference‐in‐difference analyses is then employed to empirically assess Sarbanes Oxley's impact on equity risk.

Findings

The findings suggest Sarbanes Oxley decreased both risk‐adjusted returns and upside risk, whereas downside risk fails to explain the cross section of returns for the largest US firms. From a global perspective, it is suggested that the enactment of Sarbanes Oxley's in the USA motivated leading non‐US economies to adopt similar regulatory measures, which caused “ripple effects” – e.g. effects similar to those documented in this paper – in leading non‐US economies.

Practical implications

The findings suggest that comprehensive financial regulations, such as Sarbanes Oxley Act, are properly envisaged at the global level, as their impact is not confined to the home country. In an increasingly globalized economy, investor welfare is likely to be influenced – directly as well as indirectly – by economic and financial regulation(s) enacted in foreign economies. Arguably, this suggests the pivotal importance of effective mechanisms of global governance, such that a purely domestic approach to regulation may be short‐sighted. In either case, the findings of this study are entirely relevant if regulators are to consider the broader, global impact of regulation on investor welfare.

Originality/value

This is the first study to empirically analyze, within a global framework, Sarbanes Oxley's risk implications without relying on a series of simple mean variance analyses. Substantive research documents that the methodological approach employed is more precise, reliable as well as “investor relevant”. Furthermore, the authors seek to assess the law's impact on leading non‐US equity markets, a first for the literature. Consequently, this study provides a robust evaluation of the law's (international) impact on firm (equity) risk, making an important contribution to the literature.

Citation

Vakkur, N.V. and Herrera‐Vakkur, Z.J. (2012), "Ripple effects: Sarbanes Oxley's impact upon investor risk in a global economy", Review of Accounting and Finance, Vol. 11 No. 2, pp. 184-205. https://doi.org/10.1108/14757701211228219