. spin-off downstream business on june 30 , 2011 , the spin-off of marathon 2019s downstream business was completed , creating two independent energy companies : marathon oil and mpc . marathon stockholders at the close of business on the record date of june 27 , 2011 received one share of mpc common stock for every two shares of marathon common stock held . a private letter tax ruling received in june 2011 from the irs affirmed the tax-free nature of the spin-off