Marathon Petroleum has closed its $21 billion sale of the Speedway gas station chain to 7-Eleven. The company will use part of these funds to buy back $4 billion worth of shares through a tender offer with a range of $56-63 per share, which is scheduled to be announced shortly. At the same time, the total amount of the buyback program is increased from the remaining $2.9 billion to $10 billion. Another $2.5 billion will be used to reduce the debt burden.