Gen Corp, the company that owns the rocket engine firm Aerojet, has had its $550 million planned acquisition of Pratt & Whitney Rocketdyne (PWR) from United Technologies Corp,approved after U.S. Federal Trade Commission (FTC) closed its invstigation and relaxed its objection following advice from the US Department of Defence.
http://www.ftc.gov/opa/2013/06/gencorp.shtm
While Gen Corp’s rocket engine business will now dominate the launch vehicle market (save for some SpaceX competition for full launch vehicles and competion from ATK in the solid rocket end of the business), the US Department of Defence noted that for strategic reasons the merger should not force the sale of Aerojet’s LDACS (Liquid Divert and Attitude Control Systems) business which had orginally been required for the deal to take place.