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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington D.C. 20549


FORM 6-K

Report of Foreign Issuer

Pursuant to Rule 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

For the month of May 2005 Commission File No.: 1-31349

THE THOMSON CORPORATION
(Translation of registrant's name into English)

Metro Center, One Station Place
Stamford, Connecticut 06902, United States
(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F   o   Form 40-F   ý

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):                              

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):                             

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   o   No   ý

If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-                             .





SIGNATURES

        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, thereunto duly authorized.

    THE THOMSON CORPORATION

 

 

By:

/s/  
DEIRDRE STANLEY      
Name: Deirdre Stanley
Title: Senior Vice President and General Counsel

Date: May 4, 2005

 

 

 


EXHIBIT INDEX

Exhibit Number

  Description

99.1   Press release dated May 4, 2005



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SIGNATURES
EXHIBIT INDEX