Carl Icahn reportedly plans to nominate a slew of directors to the board of SandRidge Energy Inc. (NYSE: SD)—a company the activist investor has railed against for the last several months.

Icahn, who is SandRidge Energy’s largest shareholder with a 13.5% stake, is said to also be considering making an offer to buy the Oklahoma City-based oil and gas producer.

Previously, Icahn helped to influence the ousting of SandRidge CEO James Bennett and also torpedoed the company’s proposed $746 million merger with Bonanza Creek Energy Inc. (NYSE: BCEI) in December.

In a regulatory filing, Icahn said he has “grave concerns” with the current board’s solicitation of offers for joint ventures, asset sales and mergers.

Icahn has criticized the board extensively in the past. On Jan. 9, he sent the board a fiery letter criticizing SandRidge’s leadership and tactics and demanding a shakeup of the company’s board of directors. At the time he said the boards’ hubris toward the company’s owners was tantamount to the “medieval belief in the divine right of kings.”

He and his partners said they will nominate directors who “would publicly commit to run—in a fair and timely manner—its own formal process to evaluate strategic alternatives, which would include a commitment to submit the highest and best offer to a vote of [SandRidge] stockholders.”

In the filing, he also said any new strategic reviews run by the current board, were “likely to be value destructive” and that the current board has a “history of making poor decisions on behalf of stockholders.”

He also said that upon election of the new directors, he would make an all-cash offer for the company.

“Obviously if the new board were presented with a higher offer from another party, and the reporting persons did not top it, that offer would be presented to stockholders,” Icahn said in the filing.