Energen   (EGN)  rose early Wednesday after activist investor Keith Meister and his fund Corvex Capital launched a campaign urging the oil and gas exploration and production company to consider selling itself.

The Birmingham, Ala.-based oil and gas driller's shares are up 4% to $57.85 a share on the news. 

Corvex disclosed a 5.5% stake in an activist securities filing that included a note reporting that the activist fund has had discussions with Energen about what it believes is its attractive oil and gas leaseholds in the Permian Basin. The fund also suggested that the company should "strongly consider" a review of the potential value delivered to shareholders through a change of control transaction given the recent wave of acquisitions in the Permian Basin..."

Energen comes off The Deal's Watchlist of possible activist targets. The company was put on the Watch List last week after Corvex, and three high-profile activists reported accumulating shares in the $5.2 billion Birmingham, Ala.-based oil and gas driller, according to their quarterly 13F securities filings with the Securities and Exchange Commission. At the time, Corvex reported owning a 1.4% stake, Elliott a 0.9% and Highfields accumulating $2.9 billion. The 13F disclosures were based on positions owned by each fund at the end of the first quarter, reported 45 days later in mid-May.

Since then, Corvex has tripled its stake. The fund and its representatives said they expect to continue to have conversations with the company and third parties "including both domestic and international oil and gas companies" as well as shareholders. This suggests that the activist fund is talking to other investors about whether they would support a sale as well as potential oil and gas companies in the U.S. and abroad to gauge their interest in acquiring Energen.

Meister, an activist investor who previously worked for billionaire Carl Icahn, has launched director-election contests in the past in efforts to drive M&A and other changes at targeted companies. A director battle would need to be launched by Feb. 2 to be considered for Energen's 2018 annual meeting, which is likely to take place in May. 

According to FactSet Research, Meister has launched 13 activist campaigns and four proxy fights as part of his effort to drive change at targeted companies.