SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 6-K REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934 For the month of June 2003 TRANSCANADA PIPELINES LIMITED -------------------------------------------------------------------------------- (Exact Name of Registrant as Specified in Charter) 450 - 1ST STREET S.W., CALGARY, ALBERTA, T2P 5H1, CANADA -------------------------------------------------------------------------------- (Address of Principal Executive Offices) Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F: Form 20-F Form 40-F X ---- ---- Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934. Yes No X ---- ---- The following document is hereby filed with the Securities and Exchange Commission for the purpose of being (and hereby is) incorporated by reference as an additional exhibit into Registration Statement on Form F-9 (File No. 333-101140): 4.10 Underwriting Agreement dated June 9, 2003 between TransCanada PipeLines Limited and the underwriters listed therein. SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. TRANSCANADA PIPELINES LIMITED Date: June 10, 2003 By: /s/ Rhondda E.S. Grant ------------------------------------- Name: Rhondda E.S. Grant Title: Vice-President and Corporate Secretary EXHIBIT INDEX 4.10 Underwriting Agreement dated June 9, 2003 between TransCanada PipeLines Limited and the underwriters listed therein.