EXHIBIT 12 IRREVOCABLE APPOINTMENT OF PROXY The undersigned stockholder (the "Stockholder") of Howell Corporation ("BELAIR") has executed a Support/Voting Agreement (the "Voting Agreement"), dated September 26, 2002, between the Stockholder and...Irrevocable Appointment of Proxy • December 4th, 2002 • Howell Corp /De/ • Crude petroleum & natural gas
The undersigned stockholder (the "Stockholder") of Howell Corporation ("BELAIR") has executed a Support/Voting Agreement (the "Voting Agreement"), dated September 26, 2002, between the Stockholder and Anadarko Petroleum Corporation ("PARENT"). The Voting Agreement relates to the Agreement and Plan of Merger, dated the same date, among PARENT, Belair Merger Corp. ("Subcorp") and BELAIR (the "Merger Agreement"). The Merger Agreement provides for, among other things, the merger of Subcorp with and into BELAIR (the "Merger").
