Key takeaways:

• The Delaware Court of Chancery has enjoined Martin Marietta for four months from pursuing its hostile bid for rival Vulcan Materials, citing breaches of two non-disclosure agreements.
• Although the non-disclosure agreements did not include an explicit standstill provision, under the court's analysis, their confidentiality and limited use provisions had effects tantamount to a standstill agreement.
• The court's detailed contractual analysis, which included a thorough examination of the parties' negotiating history and other extrinsic evidence, is an important reminder that parties are taking a potentially significant risk if their agreements do not clearly say what the parties mean.