This Equity Commitment Letter may not be assigned by Piceance without the prior written consent of Par (and any purported assignment without such consent will be null and void). Par may assign its commitments and agreements hereunder, in whole or in part, to any of its affiliates prior to the execution of Definitive Documentation. This Equity Commitment Letter may not be amended nor may any term or provision hereof or thereof waived or otherwise modified except by an instrument in writing signed by each of the parties hereto and any term or provision hereof or thereof may be amended or waived only by a written agreement executed and delivered by all parties hereto.