Marathon Oil (MRO)

Obligations of Each Party

3.1 Obligations of Parent. In connection with the Reorganization Agreement Parent assumed certain obligations of Old USX as listed in Schedule 3.1 hereof (the “Parent Obligations”). Parent acknowledges that it is solely responsible for all obligations including debt service under the Parent Obligations.

3.2 Contingent Obligations of Steel. Steel remains contingently liable for certain of the Parent Obligations as set forth on Schedule 3.1. Parent agrees that it will use commercially reasonable efforts to cause Steel to be released from such contingent liability and shall not increase the amounts due under such obligations (other than amounts due under revolving credit facilities that do not exceed the amounts outstanding plus the existing commitments) or extend the terms thereof without the prior written consent of Steel other than extensions set forth in the terms of any of the Parent Obligations.

3.3 Contingent Obligations of Parent. Parent remains contingently liable under the 1314B Guarantee and the Swap Guarantees. Steel agrees that it will use commercially reasonable efforts to cause Parent to be released from the 1314B Guarantee and each Swap Guarantee and shall not increase the amounts of the obligations guaranteed under the Swap Guarantees without the prior written consent of Parent. Steel further agrees to use commercially reasonable efforts to avoid causing the amount for which Parent may be liable under the 1314B Guarantee to be increased without the Parent’s prior written consent (such consent not to be unreasonably withheld).

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Obligations of Each Party