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Legal Information

This filing contains forward-looking statements that are made pursuant to the Safe Harbor Provisions of the Private Securities Litigation Reform Act of 1995, particularly those statements regarding the effects of the proposed merger and those preceded by, followed by or that otherwise include the words “believes,” “expects,” “anticipates,” “intends,” “estimates,” or similar expressions. Forward-looking statements relating to expectations about future results or events are based upon information available to Pioneer and Evergreen as of today’s date, and neither Pioneer nor Evergreen assumes any obligations to update any of these statements. The forward-looking statements are not guarantees of the future performance of Pioneer, Evergreen or the combined company, and actual results may vary materially from the results and expectations discussed. For instance, although Pioneer and Evergreen have signed an agreement for a subsidiary of Pioneer to merge with Evergreen, there is no assurance that they will complete the proposed merger. The merger agreement will terminate if the companies do not receive necessary approval of each of Pioneer’s and Evergreen’s stockholders or government approvals or fail to satisfy conditions to closing. Additional risks and uncertainties related to the proposed merger include, but are not limited to, conditions in the financial markets relevant to the proposed merger, the successful integration of Evergreen into Pioneer’s business, and each company’s ability to compete in the highly competitive oil and gas exploration and production industry. The revenues, earnings and business prospects of Pioneer and the combined company and their ability to achieve planned business objectives will be subject to a number of risks and uncertainties. These risks and uncertainties include, among other things, volatility of oil and gas prices, product supply and demand, competition, government regulation or action, foreign currency valuation changes, foreign government tax and regulation changes, litigation, the costs and results of drilling and operations, Pioneer’s ability to replace reserves, implement its business plans, or complete its development projects as scheduled, access to and cost of capital, uncertainties about estimates of reserves, quality of technical data, environmental and weather risks, acts of war or terrorism. These and other risks are identified from time to time in Pioneer’s SEC reports and public announcements.

The proposed merger will be submitted to each of Pioneer’s and Evergreen’s stockholders for their consideration, and Pioneer will file with the SEC a registration statement containing the joint proxy statement-prospectus to be used by Pioneer to solicit approval of its stockholders to issue additional stock in the merger and to be used by Evergreen to solicit the approval of its stockholders for the proposed merger. Pioneer will also file other documents concerning the proposed merger. You are urged to read the registration statement and the joint proxy statement-prospectus regarding the proposed merger when they become available and any other relevant documents filed with the SEC, as well as any amendments or supplements to those documents, because they will contain important information. You will be able to obtain a free copy of the joint proxy statement-prospectus including the registration statement, as well as other filings containing information about Pioneer at the SEC’s Internet Site (http://www.sec.gov). Copies of the joint proxy statement-prospectus can also be obtained without charge, by directing a request to: Pioneer Natural Resources Company, Susan Spratlen, 5205 N. O’Connor Blvd., Suite 900, Irving, Texas 75039, or via telephone at 972-969-3583.

Pioneer and its directors and executive officers may be deemed to be participants in the solicitation of proxies from the stockholders of Pioneer in connection with the proposed merger. Evergreen and its directors and executive officers may be deemed to be participants in the solicitation of proxies from the stockholders of Evergreen in connection with the proposed merger. Additional information regarding the interests of those participants may be obtained by reading the joint proxy statement-prospectus regarding the proposed merger when it becomes available.