<PAGE>
Janus Investment Fund
Supplement dated January 1, 2001 to
Statement of Additional Information
dated January 31, 2000,
as supplemented July 28, 2000, September 25, 2000 and December 8, 2000
THIS INFORMATION SUPPLEMENTS THE FUNDS' STATEMENT OF ADDITIONAL INFORMATION.
THIS SUPPLEMENT, ANY PREVIOUS SUPPLEMENT(S) AND THE STATEMENT OF ADDITIONAL
INFORMATION TOGETHER CONSTITUTE A CURRENT STATEMENT OF ADDITIONAL INFORMATION.
TO REQUEST ANOTHER COPY OF THE STATEMENT OF ADDITIONAL INFORMATION, PLEASE VISIT
JANUS.COM OR CALL 1-800-525-3713.
Effective January 1, 2001, if you hold Fund shares in a tax-deferred account,
you will no longer be charged the annual $12 account maintenance fee.
