A proxy firm is a company hired by corporate shareholders to cast votes on their behalf. The top three proxy firms are Proxy Governance, Inc., Glass, Lewis & Co. and RiskMetrics/Institutional Shareholder Services.[1] Some proxy firms play the role of proxy advisor, in which they simply advise their clients on how to vote.[2] A potential conflict of interest identified by the Government Accountability Office is that some owners of proxy firms do business with both issuers and investors.[3] In many cases, proxy firms have attempted to limit executive compensation.[4]