THE CORPORATE LIBRARY

Related Party Transactions and Outside Related Director Information

ONEOK, Inc. (OKE)

4/6/2006 Proxy Information

From time to time and in the normal course of business, we undertake certain transactions with Frontier Oil Corporation and its subsidiaries with respect to the purchase, sale, and transportation of natural gas and natural gas liquids. Julie H. Edwards, who was the Executive Vice President-Finance and Administration and Chief Financial Officer of Frontier Oil Corporation and its subsidiaries until May 31, 2005, was a member of our Board until her resignation effective July 1, 2005. Our transactions with Frontier are conducted on substantially the same terms as comparable third-party transactions. During 2005, we made purchases from and sales to Frontier and its subsidiaries of approximately $19,331,000 and $210,624,000, respectively.

In the normal course of business, we sell and purchase natural gas and natural gas liquids to and from Williford Energy Company and its affiliates. Mollie B. Williford, Chairman of the Board of the Williford Companies, which consists of several companies including Williford Energy Company, is a member of our Board. Our transactions with Williford Energy and its affiliates are conducted under substantially the same terms as comparable third-party transactions. During 2005, we made sales to and purchases from Williford Energy and its affiliates of approximately $101,249 and $9,393,204, respectively.

In the normal course of business, we sell natural gas to Shawnee Milling Company. William L. Ford, President of Shawnee Milling Company, is a member of our Board. During 2005, we made gas sales to Shawnee Milling Company of approximately $282,197. Our sales of natural gas to Shawnee Milling Company are made on substantially the same terms as comparable third-party transactions.

4/1/2005 Proxy Information

From time to time and in the normal course of business, we purchase natural gas liquids from and sell natural gas and natural gas liquids and provide natural gas and natural gas liquids transportation services to Frontier Oil Corporation and its subsidiaries. Julie H. Edwards, Executive Vice President-Finance and Administration and Chief Financial Officer of Frontier Oil Corporation and its subsidiaries, is a member of our Board. Our transactions with Frontier are conducted on substantially the same terms as comparable third-party transactions. During 2004, we made purchases from and sales to Frontier and its subsidiaries of approximately $17.7 million and $160.5 million, respectively.

In the normal course of business, we sell and purchase natural gas and natural gas liquids to and from Williford Energy Company and its affiliates. Mollie B. Williford, Chairman of the Board of the Williford Companies, which consists of several companies including Williford Energy Company, is a member of our Board. Our transactions with Williford Energy and its affiliates are conducted under substantially the same terms as comparable third-party transactions. During 2004, we made sales to and purchases from Williford Energy of approximately $7.7 million and $165,000, respectively.

In the normal course of business, we sell natural gas to Shawnee Milling Company. William L. Ford, President of Shawnee Milling Company, is a member of our Board. During 2004, we made gas sales to Shawnee Milling Company of approximately $217,000.

4/7/2004 Proxy Information

J. D. Scott served as President, Chief Executive Officer, and Chairman of ONEOK Inc. from January 1987 until he retired in 1994.

We are a party to a shared services agreement with Westar Industries, Inc. which provides for cooperation between the parties with respect to various services and shared facilities relating to the operations of our Kansas Gas Service Company division, such as billing, meter reading, and phone center coverage. During the year ended December 31, 2003, we made a net payment to Westar Industries, Inc. of approximately $5.1 million related to this agreement. At December 31, 2002, Westar Industries, Inc. and its parent company, Westar Energy, Inc., beneficially owned 4,714,434 shares of our common stock and 19,946,448 shares of our Series A Convertible stock which was convertible, subject to certain limitations, into 39,892,896 shares of our common stock representing, in the aggregate and assuming conversion of the Series A preferred stock into shares of our common stock, approximately 45% of our common stock. During the year ended December 31, 2003, Westar sold, in a series of transactions, all of the shares of our common and preferred stock held by Westar, and Westar no longer holds any shares of our common or preferred stock.

From time to time and in the normal course of business, we purchase natural gas liquids from and sell natural gas and natural gas liquids and provide natural gas transportation services to Frontier Oil Corporation and its subsidiaries in connection with FrontierŐs operation of its refinery in El Dorado, Kansas. Julie H. Edwards, Executive Vice President-Finance and Administration of Frontier Oil Corporation and its subsidiaries, is a member of our Board. Our transactions with Frontier are conducted on substantially the same terms as comparable third-party transactions. During 2003, we made purchases from and sales to Frontier and its subsidiaries of approximately $26.4 million and $178 million, respectively.

In the normal course of business, we purchase natural gas and natural gas liquids from Williford Energy Company and its affiliates. Mollie B. Williford, Chairman of the Board of the Williford Companies, which consists of numerous companies including Williford Energy Company, is a member of our Board. Our transactions with Williford Energy and its affiliates are conducted under substantially the same terms as comparable third-party transactions. During 2003, we made purchases from Williford Energy of approximately $516,000.

4/1/2003 Proxy Information

We are a party to a shared services agreement with Westar Industries, Inc. which provides for cooperation between the parties with respect to various services and shared facilities relating to the operations of our Kansas Gas Service Company division, such as billing, meter reading, and phone center coverage. During the year ended December 31, 2002, we made a net payment to Westar Industries, Inc. of approximately $5 million related to this agreement.