The Sarbanes-Oxley Act (SOX) was designed to improve the quality of financial reporting by public companies. It was written in response to the fraudulent reporting of Enron Corporation, Worldcom, and several other businesses, and was passed in 2002. Key provisions of the Act are as follows:
The provisions of the Act made it significantly more expensive for firms to be publicly-held. The result was a decline in the number of public companies, especially among the smaller firms that could no longer afford the regulatory costs associated with being publicly-held. In particular, the requirements of Section 404 were considered to have the largest impact on the cost increase.
The official name of the Sarbanes-Oxley Act is the Corporate Responsibility Act of 2002.
Source: Sarbanes-Oxley Act