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Cost Basis Calculator

Calculating the cost basis of your Marathon Petroleum Corporation (MPC) common stock to report capital gains taxes to the IRS can be a difficult process. To assist our shareholders in calculating their cost basis, MPC is providing a hyperlink from our website to NetBasis Cost Basis system.

For a fee, NetBasis will automatically calculate the cost basis for your Marathon Petroleum Corporation stock, by adjusting for any corporate actions or dividend reinvestments,if applicable. To use NetBasis, you will need your purchase/acquisition/salesdates and the number of shares or dollar amount acquired and/or sold on thosedates.

If you have any questions about using NetBasis, you can call their 24/7Customer Care Call Center, 1-885-55-BASIS (1-888-552-2747) or use the Live WebChat service located on the HELP button once you have logged on to the system.


Upon selecting the NetBasis icon above, you will be leaving Marathon Petroleum Corporation's website and will be redirected to the NetBasis system. Marathon Petroleum Corporation receives no compensation from NetBasis or Networth Services, Inc., the owners of NetBasis. Marathon Petroleum Corporation shall have no liability for any information received from the NetBasis system.