Callon Investor Sues to Halt Vote on $4.5 Billion Sale to APA

An investor sued Callon Petroleum Co., seeking to block a shareholder vote on its planned $4.5 billion sale to fellow oil and gas company APA Corp. over allegedly inadequate deal-related disclosures.

The lawsuit, filed Monday in Delaware’s Chancery Court, seeks an injunction against the March 27 vote until Houston-based Callon provides more information about a competing bid, potential conflicts of interest, and synergy estimates for the transaction.

“Once defendants travel down the road of partial disclosure of the history leading up to the merger, they have an obligation to provide stockholders with an accurate, full, and fair characterization,” according ...