OKLAHOMA CITY (AP) - The board of directors of SandRidge Energy Inc. is asking shareholders to reject a proposal to oust the board.

The Oklahoma City-based company said in a regulatory filing Thursday that the proposal by TPG-Axon would force SandRidge to offer to buy back all its outstanding at a cost of $4.3 billion. The filing says SandRidge would also lose $775 million in available borrowing.

The board also called TPG-Axon - which owns about 6.7 percent of SandRidge stock - an "opportunistic investor with short-term interests."

TPG-Axon spokesman Anton Nicholas told The Oklahoman that it has been investing in the company for more than a year.

TPG-Axon says SandRidge is undervalued and blamed the board. SandRidge stock was down 6 cents to $6.35 per share in early trading Friday.

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