Oil and Gas Exploration and Production Business Contracts

Apache Corp.

• 5151 San Felipe Road (Houston, TX) Sublease Agreement - Apache Corp. and IWC Services Inc. (Oct 18, 2009)
• Retirement Plan - Outside Directors - Apache Corp. (Jan 03, 2012)
• Omnibus Equity Compensation Plan - Apache Corp. (Jan 03, 2012)
• 401(k) Savings Plan - Apache Corp. (Jan 03, 2012)
• Bylaws - Apache Corp. (Jan 03, 2012)
• Underwriting Agreement - Apache Corp. (Jan 03, 2012)

Brown Tom Inc.

• Registration Rights Agreement - Tom Brown Inc. and K N Energy Inc. (Oct 18, 2009)
• Stock Ownership and Registration Rights Agreement - Union Oil Co. of California and Tom Brown Inc. (Oct 18, 2009)
• 1999 Long Term Incentive Plan - Tom Brown Inc. (Oct 18, 2009)
• 401(k) Retirement Plan - Tom Brown Inc. (Oct 18, 2009)
• 1993 Stock Option Plan - Tom Brown Inc. (Oct 18, 2009)
• Employment Agreement - Tom Brown Inc. and James D. Lightner (Oct 18, 2009)
• Employment Agreement - Tom Brown Inc. and Donald L. Evans (Oct 18, 2009)
• Severance Agreements - Tom Brown Inc. and Donald L. Evans, William R. Granberry, Peter R. Scherer, Thomas W. Dyk, Bruce R. DeBoer, Clifford C. Drescher, Richard B. Porter, R. Kim Harris, B. Jack Reed and William H. Munn II (Oct 18, 2009)
• Severance Plan - Tom Brown Inc. (Oct 18, 2009)
• Employment Agreement - Tom Brown Inc. and Donald L. Evans (Oct 18, 2009)
• Severance Agreement - Tom Brown Inc. (Oct 18, 2009)
• Deferred Compensation Plan - Tom Brown Inc. (Oct 18, 2009)
• 1993 Stock Option Plan - Tom Brown Inc. (Oct 18, 2009)
• 1999 Long Term Incentive Plan - Tom Brown Inc. (Oct 18, 2009)
• Severance Plan - Tom Brown Inc. (Oct 18, 2009)
• Certificate of Incorporation - Tom Brown Inc. (Oct 18, 2009)
• Wild Horse Limited Liability Company Agreement - K N Energy Inc. and Tom Brown Inc. (Oct 18, 2009)
• Certificate of Incorporation - Tom Brown Inc. (Oct 18, 2009)
• Exchange Agreement - Presidio Oil Co., Presidio Exploration Inc., Presidio West Virginia Inc., Palisade Oil inc and Tom Brown Inc. (Oct 18, 2009)
• Exchange Agreement - Presidio Oil Co., Presidio Exploration Inc., Presidio West Virginia, Palisade Oil Inc. and Tom Brown Inc. (Oct 18, 2009)
• Agreement and Plan of Reorganization - Tom Brown Inc., K N Production Co. and K N Energy Inc. (Oct 18, 2009)
• Purchase and Sale Agreement - Union Oil Co. of California and Tom Brown Inc. (Oct 18, 2009)
• Purchase and Sale Agreement - Genesis Gas & Oil LLC and TBI Production Co. (Oct 18, 2009)
• Exchange Agreement - Presidio Oil Co., Presidio Exploration Inc., Presidio West Virginia, Palisade Oil Inc. and Tom Brown Inc. (Oct 18, 2009)
• Exchange Agreement - Presidio Oil Co., Presidio Exploration Inc., Presidio West Virginia, Palisade Oil Inc. and Tom Brown Inc. (Oct 18, 2009)
• Pre-Acquisition Agreement - Tom Brown Inc. and Stellarton Energy Corp. (Oct 18, 2009)
• Credit Agreement - Tom Brown Inc., Chase Manhattan Bank, NationsBank of Texas NA and U.S. Bank NA (Oct 18, 2009)
• Credit Agreement - Tom Brown Inc., Chase Manhattan Bank, Bank of America NA, U.S. Bank NA and Bank of Nova Scotia (Oct 18, 2009)

Chevron Corp.

• Class B Stock Purchase Agreement - Dynegy Inc. and Chevron U.S.A. Inc. (Oct 18, 2009)
• Shareholder Agreement - Dynegy Inc. and Chevron U.S.A. Inc. (Oct 18, 2009)
• Chevron Form 8-K (Jul 28, 2011)
• Long-Term Incentive Award Agreement - Chevron (Dec 19, 2011)
• Restricted Stock Unit Award Agreement - Chevron (Dec 19, 2011)
• Retainer Stock Option Agreement - Chevron (Dec 19, 2011)
• Employment Agreement with Charles A. James - Chevron (Dec 20, 2011)
• Termination Agreement with Charles A. James - Chevron (Dec 20, 2011)
• Amended and Restated Bylaws - Chevron (Dec 19, 2011)
• Chevron Form 11-K (Jul 28, 2011)
• Chevron Financial Statement on Tax Deferred Savings Plan (Jul 28, 2011)

ChevronTexaco Corp.

• Purchase Rights Agreement - Dynegy Inc and ChevronTexaco Corp. (Oct 18, 2009)

Dynegy Inc.

• Class B Stock Purchase Agreement - Dynegy Inc. and Chevron U.S.A. Inc. (Oct 18, 2009)
• Shareholder Agreement - Dynegy Inc. and Chevron U.S.A. Inc. (Oct 18, 2009)
• Agreement and Plan of Merger - Dynegy Inc. and Enron Corp. (Oct 18, 2009)
• Purchase Rights Agreement - Dynegy Inc and ChevronTexaco Corp. (Oct 18, 2009)
• Agreement and Consent - Dynegy Inc., Enron Corp., Northern Natural Gas Co., Citicorp U.S.A. Inc., JPMorgan Chase Bank (Oct 18, 2009)
• Exchange Agreement - Dynegy Inc. and Enron Corp. (Oct 18, 2009)
• Exchange Agreement (Amendment) - Dynegy Inc. and Enron Corp. (Oct 18, 2009)
• Option Agreement - Enron Corp. and Dynegy Inc. (Oct 18, 2009)
• Purchase Option Agreement - Enron Corp. Dynegy Inc., Northern Natural Gas Co. (Oct 18, 2009)
• Purchase Option Agreement (Amendment) - Enron Corp., Dynegy Inc., Northern Natural Gas Co. (Oct 18, 2009)
• By-Laws - Dynegy Inc. (Oct 18, 2009)

Harken Oil & Gas Inc.

• Partial Settlement and Conversion Agreement - Joseph F. Langston Jr. and Search Exploration Inc. (Oct 18, 2009)
• Assignment of Overriding Royalty Interest - Langston Investments Inc. and Search Exploration Inc. (Oct 18, 2009)
• Assignment of Overriding Royalty Interest - O'Donnell & Masur and Search Exploration Inc. (Oct 18, 2009)
• Assignment of Overriding Royalty Interest - Dobbins Partners LP and Search Exploration Inc. (Oct 18, 2009)
• Partial Settlement and Conversion Agreement - EnCap Investments LC and Search Exploration Inc. (Oct 18, 2009)
• Partial Settlement and Conversion Agreement - Concorde Financial Corp. and Search Exploration Inc. (Oct 18, 2009)
• Association Contract - Empresa Colombiana de Petroleos (ECOPETROL) and Harken de Colombia Ltd. (Oct 18, 2009)
• Drilling Contract - Harken de Colombia Ltd. and Marlin Colombia Drilling Co. Inc. (Oct 18, 2009)
• Drilling Contract - Harken de Colombia Ltd. and Parker Drilling Co. Intl. Ltd. (Oct 18, 2009)
• Association Contract - Empresa Colombiana de Petroleos (ECOPETROL) and Harken de Colombia Ltd. (Oct 18, 2009)
• Association Contract - Empresa Colombiana de Petroleos (ECOPETROL) and Harken de Colombia Ltd. (Oct 18, 2009)
• Association Contract - Empresa Colombiana de Petroleos (ECOPETROL) and Harken de Colombia Ltd. (Oct 18, 2009)
• Agreement and Plan of Merger - Harken Energy Co. and Xplor Energy Inc. (Oct 18, 2009)
• Asset Purchase and Sale Agreement - St. Martinville Partners Ltd., Bargo Energy Co., Harken Energy Corp. and Harken Exploration Co. (Oct 18, 2009)
• Agreement and Plan of Merger - Harken Energy Corp. and Search Exploration inc. (Oct 18, 2009)
• Securities Purchase Agreement - Harken Energy Corp. and RGC International Investors LDC (Oct 18, 2009)
• Exchange Agreement - Harken Energy Corp., Harken Capital Corp., Sidro SA, Lambertine Holdings Ltd. and Rauscher Pierce & Clark (Guernsey) Ltd. (Oct 18, 2009)
• Exchange Agreement - Momentum Operating Co. and Harken Exploration Co. (Oct 18, 2009)
• Acquisition Proposal Letter - Huffco Group Inc. and Harken de Colombia Ltd. (Oct 18, 2009)
• Asset Purchase and Sale Agreement - Enervest Acquisition-II LP, Harken Energy Corp. and Harken Exploration Co. (Oct 18, 2009)
• Purchase and Sale Agreement - Momentum Operating Co., Harken Exploration Co. and Harken Energy Corp. (Oct 18, 2009)
• Agreement of Sale and Purchase - Yellowhouse Project Co. and Harken Energy West Texas Inc. (Oct 18, 2009)
• Concession and Lease Purchase Agreement - Paroo Petroleum (USA) Inc. and Harken Energy Corp. (Oct 18, 2009)
• Concession and Lease Purchase Agreement - C A B Resources Inc., Crusader Inc., Australian Hydrocarbons Inc. and Harken Energy Corp. (Oct 18, 2009)
• Purchase and Sale Agreement - Republic Resources Inc. and Harken Energy Corp. (Oct 18, 2009)
• Development Finance Agreement - Harken Energy Corp. and Harken Capital Corp. (Oct 18, 2009)
• Development Finance Agreement - Harken Energy Corp., EnCap Energy Capital Fund III LP, EnCap Energy Capital Fund III-B LP, BOCP Energy Partners LP and Energy Capital Investment Co. (Oct 18, 2009)
• Promissory Note - Harken Exploration Co. and Momentum Operating Co. Inc. (Oct 18, 2009)
• Development Finance Agreement - Harken Energy Corp., Arbco Associates LP, Offense Group Associates LP, Kayne, Anderson Nontraditional Investments LP and Opportunity Associates LP (Oct 18, 2009)
• Restructuring and Sale Agreement - Harken Energy Corp., Harken Energy West Texas Inc., Internationale Nederlanden (U.S.) Capital Corp., New England Mutual Life Insurance Corp., and EnCap 1989-I LP (Oct 18, 2009)
• Rights Agreement - Harken Energy Corp. and ChaseMellon Shareholder Services LLC (Oct 18, 2009)

Hess Corp.

• Form Restricted Stock Award Agreement - Hess (Oct 12, 2011)
• Form Stock Option Agreement - Hess (Oct 12, 2011)
• Amended and Restated Termination Benefits Agreement - Hess (Oct 12, 2011)
• General Counsel Employment Offer - Hess (Oct 12, 2011)
• Amended and Restated Change in Control Agreement with Walker - Hess (Oct 13, 2011)
• Amended and Restated Change in Control Agreement with Bohling - Hess (Oct 13, 2011)
• Letter Report on Proved Reserve Audit - Hess (Oct 13, 2011)

Occidental Petroleum Corp.

• Underwriting Agreement - Occidental Petroleum Corp. (Feb 22, 2012)
• Note - Occidental Petroleum Corp. (Feb 22, 2012)
• Certificate of Incorporation - Occidental Petroleum Corp. (Oct 18, 2009)
• Officers' Certificate - Occidental Petroleum Corp. (Feb 22, 2012)
• Purchase and Sale Agreement - Amoco D.T. Co., Amoco X.T. Co, Amoco Y.T. Co, SWEPI LP, Shell Land & Energy Co, Shell Onshore Ventures Inc., Shell K2 Inc., Shell Everest Inc. and Occidental Petroleum Corp. (Oct 18, 2009)
• Acknowledgment Letter - Effect of Write-Down on Return on Equity Incentive Award - Occidental Petroleum Corp. (Feb 22, 2012)
• Employment Agreement - President - Occidental Petroleum Corp. (Feb 22, 2012)
• Long-Term Incentive Award Agreement - Occidental Petroleum Corp. (Feb 22, 2012)

Republic Resources Inc.

• Purchase and Sale Agreement - Republic Resources Inc. and Harken Energy Corp. (Oct 18, 2009)

Titan Exploration Inc.

• Business Opportunities Agreement - Union Oil Co. of California and Titan Exploration Inc. (Oct 18, 2009)
• Agreement and Plan of Merger - Union Oil Co. of California and Titan Exploration Inc. (Oct 18, 2009)

Unocal Corp.

• Stock Ownership and Registration Rights Agreement - Union Oil Co. of California and Tom Brown Inc. (Oct 18, 2009)
• Business Opportunities Agreement - Union Oil Co. of California and Titan Exploration Inc. (Oct 18, 2009)
• Agreement and Plan of Merger - Union Oil Co. of California and Titan Exploration Inc. (Oct 18, 2009)
• Change in Control Agreement - Unocal Corp. and Timothy H. Ling (Oct 18, 2009)
• Consulting and Settlement Agreement - Unocal Corp. and Roger C. Beach (Oct 18, 2009)
• Purchase and Sale Agreement - Union Oil Co. of California and Tom Brown Inc. (Oct 18, 2009)

Vastar Resources Inc.

• Formation Agreement - SEI Holdings Inc. and Vastar Resources Inc. (Oct 18, 2009)