SandRidge Files for IPO

SandRidge Energy Inc. (f.k.a. Riata Energy), an Oklahoma City-based oil and gas exploration and production company, has filed for a $690 million IPO. It plans to trade on the NYSE under ticker symbol SD, with Lehman Brothers serving as lead underwriter. Ares Management holds a 12.3% ownership stake, based on a $250 million common stock investment it made earlier this year. SandRidge filed for a $276 million IPO last year, but later withdrew its registration.