The National Organization for Women, Inc. (NOW) (defendant), called for its members to avoid holding conventions in states that had not ratified the proposed Equal Rights Amendment. NOW hoped that the economic boycott on conventions would persuade state legislatures to adopt the Equal Rights Amendment, which NOW saw as instrumental in expanding the legal rights of women. The State of Missouri (plaintiff) was one of the boycotted states. In response to the boycott, Missouri brought a suit against NOW, arguing that the boycott was a conspiracy to restrain trade in violation of § 1 of the Sherman Act. The district court held in favor of NOW, finding that the boycott was protected from antitrust liability under an exception for legitimate attempts to petition the government. The court of appeals affirmed, and Missouri appealed the decision.