A complex filing with the Securities and Exchange Commission (SEC) in which one party to a merger is a reporting company. Merger proxies are chiefly used to disclose the terms, background, and effects of the proposed deal. For example, they contain information about price, form of exchange, organizational structure, financial and tax impact of the deal, requirements for completion, fairness opinions, regulatory matters, and conditions of terminations. Typically, merger proxies do not divulge sensitive information to competitors, and are only drafted in a way to allow stockholders vote wisely.