Shares of Cimarex fell 6 percent to $83,
while those of Resolute, which have been down 3 percent so far this year, rose 9 percent to $33.25 before the opening bell.
Oil and gas producer Cimarex Energy Co said on Monday it would
buy smaller rival Resolute Energy Corp in a deal valued at $1.6 billion, including debt, adding more assets in the shale-rich Permian Basin.
As part of the deal, Resolute shareholders have the option to receive 0.3943 shares of Cimarex common stock,
$35 per share in cash, or a combination of $14 per share in cash and 0.2366 share of Cimarex common stock.