Multiple agencies of the US government, notably the Securities & Exchange Commission.. Also the Public Company Accounting Oversight Board.

http://www.gpo.gov/fdsys/pkg/PLAW-107publ204/content-detail.html

The Sarbanes-Oxley Act of 2002, commonly called Sarbanes-Oxley, Sarbox or SOX, is a United States federal law which set new or enhanced financial reporting and related standards for all U.S. public company boards, management and public accounting firms. The Act mandated a number of reforms to enhance corporate responsibility, enhance financial disclosures and combat corporate and accounting fraud, and created the Public Company Accounting Oversight Board, also known as the PCAOB, to oversee the activities of the auditing profession.

Title I establishes the Public Company Accounting Oversight Board to provide independent oversight of public accounting firms providing audit services ("auditors"). Title II establishes standards for external auditor independence, to limit conflicts of interest. Title III mandates that senior executives take individual responsibility for the accuracy and completeness of corporate financial reports. Title IV describes enhanced reporting requirements for financial transactions, including off-balance-sheet transactions, pro-forma figures and stock transactions of corporate officers. Title V defines the codes of conduct for securities analysts and requires disclosure of knowable conflicts of interest. Title VI defines the SEC's authority to censure or bar securities professionals from practice. Title VII requires the Comptroller General and the SEC to perform various studies and report their findings. Title VIII describes specific criminal penalties for manipulation, destruction or alteration of financial records or other interference with investigations, while providing certain protections for whistle-blowers. Title IX increases the criminal penalties associated with white-collar crimes and conspiracies. Title X states that the Chief Executive Officer should sign the company tax return. Title XI identifies corporate fraud and records tampering as criminal offenses and joins those offenses to specific penalties.

The Sarbanes Oxley Act Community Forum

U.S. public company boards, management and public accounting firms, securities analysts.

http://en.wikipedia.org/wiki/Sarbanes%E2%80%93Oxley_Act