Exhibit 99.1

Marathon Petroleum Reports First-Quarter 2012 Results

FINDLAY, Ohio, May 1, 2012 – Marathon Petroleum Corporation (NYSE:MPC) today reported first quarter net income of $596 million, or $1.70 per diluted share, compared with net income of $529 million, or $1.48 per diluted share, in the first quarter of 2011.

“Our first-quarter results reflect excellent performance by our Refining & Marketing segment as well as solid earnings contributions from our Speedway and Pipeline Transportation businesses,” said MPC President and Chief Executive Officer Gary R. Heminger. He attributed the strong Refining & Marketing segment results to the company’s ability to capture value from changing market dynamics and acquire price-advantaged crude oil and feedstocks. “Our operational flexibility and efficiency, coupled with the location of our processing capacity, allowed us to take advantage of changing crude differentials in the quarter,” Heminger stated.

Heminger pointed to MPC’s Speedway convenience store subsidiary as another strong contributor during the first quarter, noting that the retail segment had increased its volumes and margins in both fuels and merchandise sales.

Also during the first quarter, the company commenced the $2 billion share repurchase program authorized by its board of directors in January. “We have received a majority of the shares from our $850 million accelerated share repurchase program, and expect to complete this initial tranche in the coming months,” Heminger said. “This is a significant component of our plans to return capital to shareholders as we continue to pursue our balanced and disciplined approach to capital allocation.”

Heminger noted that other MPC initiatives to enhance value are also well under way. “Our separate announcement earlier today, providing an update on the status of our evaluation of strategic alternatives relative to our midstream assets, further demonstrates our commitment to pursuing opportunities to create near- and long-term value for our shareholders,” he said. “On the retail side, we are moving forward with Speedway’s acquisition of 88 GasAmerica convenience stores, which is expected to be finalized in the second quarter, solidifying our presence along major transportation corridors in Ohio and Indiana. The Speedway team continues to operate very well, and we expect they will generate solid value with these new assets. Our Detroit Heavy Oil Upgrade Project, which is designed to lower feedstock costs and capture value from crude oil differentials, is on budget and on schedule for completion in the third quarter. At the same time, we are working to enhance our infrastructure to be able to move crude oil and feedstocks from the Utica Shale play to our Canton and Catlettsburg refineries.”

Segment Results

Total income from operations was $956 million in the first quarter of 2012, compared with $819 million in the first quarter of 2011.

Refining & Marketing

Refining & Marketing segment income from operations was $943 million in the first quarter of 2012, compared with $802 million in the first quarter of 2011. The $141 million increase was primarily the result of a higher Refining & Marketing gross margin, which increased to $8.36 per barrel in the first quarter of 2012 from $6.73 per barrel in the first quarter of 2011. The primary factors contributing to the increase in the gross margin were higher U.S. Gulf Coast crack spreads and favorable crude oil acquisition costs resulting from a wider differential between West Texas Intermediate and Light Louisiana Sweet crude oils. Refining & Marketing crude oil capacity utilization was lower in the first quarter of 2012; however, total throughputs were relatively unchanged.

As of March 31, 2012, the Detroit Heavy Oil Upgrade Project was 92 percent complete and remains on budget and on schedule for an expected construction completion in the third quarter of 2012. Immediately following, there will be a 70-day turnaround with the expanded refinery anticipated to be online by year-end.

Speedway

Speedway segment income from operations was $50 million in the first quarter of 2012, compared with $33 million in the first quarter of 2011. The $17 million increase was primarily the result of a higher merchandise gross margin. Speedway same-store merchandise sales increased 2 percent in the first quarter of 2012, compared with an increase of 1.7 percent in the first quarter of 2011.

Speedway gasoline and distillate gross margin per gallon averaged 10.96 cents in the first quarter of 2012, compared with 10.64 cents in the first quarter of 2011. Same-store gasoline sales volume at Speedway decreased 1.1 percent in the first quarter of 2012, compared with a decrease of 0.2 percent in the first quarter of 2011.

Pipeline Transportation

Pipeline Transportation segment income from operations of $42 million in the first quarter of 2012 was $9 million lower than the first quarter of 2011. The decrease was primarily due to a decrease in pipeline affiliate income.

Corporate Items

Corporate and other expenses increased $12 million in the first quarter of 2012 to $79 million, compared with the first quarter of 2011. The increase is primarily due to higher employee benefits, incentive compensation and information technology expenses, which are partially the result of additional costs associated with being a stand-alone public company.

Strong Financial Position and Liquidity

On March 31, 2012, the company had $2.2 billion in cash and cash equivalents, an unused $2 billion revolving credit agreement and a $1 billion unused trade receivables securitization facility. The company’s credit facilities and cash position should provide the company with significant flexibility to meet its day-to-day operational needs and continue its balanced approach to investing in the business and returning capital to shareholders. As of March 31, 2012, the company’s strong financial position was further reflected by its debt-to-total-capital ratio of 26 percent.

Conference Call

At 10 a.m. EDT today, MPC will hold a webcast and conference call to discuss the earnings release and provide an update on company operations. Interested parties may listen to the conference call on MPC’s website at http://www.marathonpetroleum.com by clicking on the “2012 First-Quarter Financial Results” link. Replays of the conference call will be available on the company’s website through Wednesday, May 16. Financial information, including the earnings release and other investor-related material, will also be available online prior to the webcast and conference call at http://ir.marathonpetroleum.com in the Quarterly Investor Packet and Earnings Capsule.

###

About Marathon Petroleum Corporation

MPC is the nation’s fifth-largest refiner, with a crude capacity of approximately 1.2 million barrels per calendar day in its six-refinery system. Marathon brand gasoline is sold through more than 5,000 independently owned retail outlets across 18 states. In addition, Speedway LLC, an MPC subsidiary, owns and operates the nation’s fourth largest convenience store chain, with approximately 1,370 convenience stores in seven states. MPC also owns, leases or has ownership interests in approximately 8,300 miles of pipeline. MPC’s fully integrated system provides operational flexibility to move crude oil, feedstocks and petroleum-related products efficiently through the company’s distribution network in the Midwest, Southeast and Gulf Coast regions. For additional information about the company, please visit our website at http://www.marathonpetroleum.com.

Investor Relations Contacts:

Pamela Beall (419) 429-5640

Beth Hunter (419) 421-2559

Media Contacts:

Angelia Graves (419) 421- 2703

Jamal Kheiry (419) 421-3312

This release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements relate to, among other things, MPC’s current expectations, estimates and projections concerning MPC business and operations. You can identify forward-looking statements by words such as “anticipate,” “believe,” “estimate,” “expect,” “forecast,” “project,” “could,” “may,” “should,” “would” or other similar expressions that convey the uncertainty of future events or outcomes. Such forward-looking statements are not guarantees of future performance and are subject to risks, uncertainties and other factors, some of which are beyond the company’s control and are difficult to predict. Factors that could cause actual results to differ materially from those in the forward-looking statements include: further volatility in and/or degradation of market and industry conditions; the availability and pricing of crude oil and other feedstocks; slower growth in domestic and Canadian crude supply; completion of pipeline capacity to areas outside the U.S. Midwest; consumer demand for refined products; changes in governmental regulations; transportation logistics; the availability of materials and labor, delays in obtaining necessary third-party approvals, and other risks customary to construction projects; the reliability of processing units and other equipment; our ability to successfully implement growth opportunities; impacts from our repurchases of shares of MPC common stock under our stock repurchase program, including the timing and amounts of any common stock repurchases; the risk that the midstream asset evaluation may not result in the pursuit or consummation of any transaction; other risk factors inherent to our industry; and the factors set forth under the heading “Risk Factors” in MPC’s Annual Report on Form 10-K for the year ended December 31, 2011 filed with the Securities and Exchange Commission (the “SEC”). In addition, the forward-looking statements included herein could be affected by general domestic and international economic and political conditions. Unpredictable or unknown factors not discussed here or in MPC’s Form 10-K could also have material adverse effects on forward-looking statements. Copies of MPC’s Form 10-K are available on the SEC website, at http://www.ir.marathonpetroleum.com or by contacting MPC’s Investor Relations Office.

Supplemental Statistics (Unaudited)

Supplemental Statistics (Unaudited) (continued)

Segment Earnings Before Interest, Taxes, Depreciation & Amortization (Segment EBITDA)

Select Financial Data (Unaudited)