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Commission File No.: 0-29954



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 January 2003

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

Suite 2706, Toronto Dominion Bank Tower
P.O. Box 24, 66 Wellington St. West
Toronto-Dominion Centre
Toronto, Ontario
M5K 1A1, Canada

(Address of principal executive offices)

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 whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission 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-.

EXHIBIT INDEX IS LOCATED AT PAGE 2 OF 4




Information furnished on this form:

Press Release dated January 23, 2003 of The Thomson Corporation entitled "John M. Thompson Joins Board of The Thomson Corporation".


EXHIBIT

Exhibit
Number

   
  Page
1.   Press Release dated January 23, 2003.   4

2



SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements contained in Exhibit number 1 constitute forward-looking statements, which are based on the Corporation's current expectations and assumptions, and are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated. Such risks and uncertainties include, among others, general business and economic conditions and competitive actions.


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
(Registrant)

Date: January 24, 2003

/s/  
PAULA R. MONAGHAN      
Assistant Secretary

3




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EXHIBIT
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
SIGNATURES

The Thomson Corporation
Metro Center, One Station Place
Stamford, CT 06902
Tel (203) 969-8700 Fax (203) 977-8354
www.thomson.com
  LOGO

News Release

Investor Contact:

  Media Contact:

John Kechejian   Jason Stewart
Vice President, Investor Relations   Director, Public Relations
(203) 328-9470   (203) 328-8339
john.kechejian@thomson.com   jason.stewart@thomson.com

For Immediate Release


JOHN M. THOMPSON JOINS BOARD OF
THE THOMSON CORPORATION


(Unless otherwise stated, all amounts are in US dollars)

STAMFORD, Conn. and TORONTO, January 23, 2003 — John M. Thompson has been appointed to the Board of Directors of The Thomson Corporation (TSX:TOC; NYSE:TOC). Mr. Thompson, age 60, is the recently retired Vice Chairman of the IBM Corporation Board of Directors and, effective April 2003, will be Lead Director and Chairman of the Board of TD Bank Financial Group. Mr. Thompson's appointment to the Thomson Board is effective immediately.

        Mr. Thompson has led a distinguished 34-year career with IBM, in which he has been responsible for identifying and cultivating major growth initiatives for the Corporation. From 1995 to 2000, Mr. Thompson served as Senior Vice President and Group Executive of IBM's Software Group. Prior, Mr. Thompson served as Senior Vice President in charge of IBM's Server Group (1993); Corporate Vice President of Marketing (1991); and President and Chief Executive Officer of IBM Canada, Ltd. (1986).

        Mr. Thompson is also a director of the Robert Mondavi Corporation.

The Thomson Corporation

The Thomson Corporation, with 2001 revenues of $7.2 billion, is a global leader in providing integrated information solutions to business and professional customers. Thomson provides value-added information, software tools and applications to more than 20 million users in the fields of law, tax, accounting, financial services, higher education, reference information, corporate training and assessment, scientific research and healthcare. The Corporation's common shares are listed on the Toronto and New York stock exchanges (TSX: TOC; NYSE: TOC).

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