Chesapeake Energy ($CHK) and Southwestern Energy ($SWN) have announced a delay in the closing date of their proposed $7.4 billion merger to the second half of the year, following a second request for information from a U.S. regulator. The Federal Trade Commission (FTC) has sought more details, prompting the companies to postpone the merger process. This development comes amid broader scrutiny of mergers and acquisitions in the energy sector by federal authorities.