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FILED PURSUANT TO RULE 424(b)(3) AND (c)
FILE NUMBER 333-61413
TWENTY-FIFTH PROSPECTUS SUPPLEMENT TO PROSPECTUS
DATED AUGUST 24, 1998
8,370,248 SHARES
LYCOS, INC.
COMMON STOCK
This Twenty-Fifth Prospectus Supplement (the "Twenty-Fifth Prospectus
Supplement") supplements the Prospectus dated August 24, 1998 (the
"Prospectus"), the Prospectus Supplement dated September 15, 1998 (the "First
Prospectus Supplement"), the Second Prospectus Supplement dated October 28, 1998
(the "Second Prospectus Supplement"), the Third Prospectus Supplement dated
November 12, 1998 (the "Third Prospectus Supplement"), the Fourth Prospectus
Supplement dated November 18, 1998 (the "Fourth Prospectus Supplement"), the
Fifth Prospectus Supplement dated November 19, 1998 (the "Fifth Prospectus
Supplement"), the Sixth Prospectus Supplement dated December 1, 1998 (the "Sixth
Prospectus Supplement"), the Seventh Prospectus Supplement dated December 2,
1998 (the "Seventh Prospectus Supplement"), the Eighth Prospectus Supplement
dated December 4, 1998 (the "Eighth Prospectus Supplement"), the Ninth
Supplement dated December 21, 1998 (the "Ninth Prospectus Supplement"), the
Tenth Prospectus Supplement dated December 28, 1998 (the "Tenth Prospectus
Supplement"), the Eleventh Prospectus Supplement dated January 14, 1999 (the
"Eleventh Prospectus"), the Twelfth Prospectus Supplement dated February 12,
1999 (the "Twelfth Prospectus Supplement"), the Thirteenth Prospectus Supplement
dated March 2, 1999 (the "Thirteenth Prospectus Supplement"), the Fourteenth
Prospectus Supplement dated March 25, 1999 (the "Fourteenth Prospectus
Supplement"), the Fifteenth Prospectus Supplement dated April 27, 1999 (the
"Fifteenth Prospectus"), the Sixteenth Prospectus Supplement dated June 16, 1999
(the "Sixteenth Prospectus Supplement"), the Seventeenth Prospectus Supplement
dated July 6, 1999 (the "Seventeenth Prospectus Supplement"), the Eighteenth
Prospectus Supplement dated July 8, 1999 (the "Eighteenth Prospectus
Supplement"), the Nineteenth Prospectus Supplement dated July 19, 1999 (the
"Nineteenth Prospectus Supplement"), the Twentieth Prospectus Supplement dated
August 26, 1999 (the "Twentieth Prospectus Supplement"), the Twenty-First
Prospectus Supplement dated September 9, 1999 (the "Twenty-First Prospectus
Supplement"), the Twenty-Second Prospectus Supplement dated September 17, 1999
(the "Twenty-Second Prospectus Supplement"), the Twenty-Third Prospectus
Supplement dated October 6, 1999 (the "Twenty-Third Prospectus Supplement"), and
the Twenty-Fourth Prospectus Supplement dated October 13, 1999
(the "Twenty-Fourth Prospectus Supplement") of Lycos, Inc. ("Lycos" or
the "Company") relating to the public offering, which is not being underwritten,
and sale of up to 8,370,248 shares of Common Stock, par value $0.01 per share
(the "Shares") of the Company, which may be offered and sold from time to time
by certain stockholders of the Company or by pledgees, donees, transferees or
other successors in interest that receive such shares as a gift, partnership
distribution or other non-sale related transfer (the
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"Selling Stockholders"). The Company will receive no part of the proceeds of
such sales. The Shares were originally issued or reserved for issuance by the
Company in connection with the Company's acquisition of WhoWhere? Inc., a
California corporation, by and through a merger of a wholly-owned subsidiary of
Lycos, What Acquisition Corp., with and into WhoWhere? Inc. (the "Acquisition").
The "Selling Stockholders" Section of the Prospectus, the First Prospectus
Supplement, the Second Prospectus Supplement, the Third Prospectus Supplement,
the Fourth Prospectus Supplement, the Fifth Prospectus Supplement, the Sixth
Prospectus Supplement, the Seventh Prospectus Supplement, the Eighth Prospectus
Supplement, the Ninth Prospectus Supplement, the Tenth Prospectus Supplement,
the Eleventh Prospectus Supplement, the Twelfth Prospectus Supplement, the
Thirteenth Prospectus Supplement, the Fourteenth Prospectus Supplement, the
Fifteenth Prospectus Supplement, the Sixteenth Prospectus Supplement, the
Seventeenth Prospectus Supplement, the Eighteenth Prospectus Supplement, the
Nineteenth Prospectus Supplement, the Twentieth Prospectus Supplement, the
Twenty-First Prospectus Supplement, the Twenty-Second Prospectus Supplement, the
Twenty-Third Prospectus Supplement and the Twenty-Fourth Prospectus Supplement
are hereby supplemented to reflect the gift made by Thomas C.K. Yuen to The UCI
Foundation in the amount of 750 shares after the date of the Prospectus, the
First Prospectus Supplement, the Second Prospectus Supplement, the Third
Prospectus Supplement, the Fourth Prospectus Supplement, the Fifth Prospectus
Supplement, the Sixth Prospectus Supplement, the Seventh Prospectus Supplement,
the Eighth Prospectus Supplement, the Ninth Prospectus Supplement, the Tenth
Prospectus Supplement, the Eleventh Prospectus Supplement, the Twelfth
Prospectus Supplement, the Thirteenth Prospectus Supplement, the Fourteenth
Prospectus Supplement, the Fifteenth Prospectus Supplement, the Sixteenth
Prospectus Supplement, the Seventeenth Prospectus Supplement, the Eighteenth
Prospectus Supplement, the Nineteenth Prospectus Supplement, the Twentieth
Prospectus Supplement, the Twenty-First Prospectus Supplement, the Twenty-Second
Prospectus Supplement, the Twenty-Third Prospectus Supplement and the
Twenty-Fourth Prospectus Supplement. This Twenty-Fifth Prospectus Supplement
should be read in conjunction with the Prospectus, the First Prospectus
Supplement, the Second Prospectus Supplement, the Third Prospectus Supplement,
the Fourth Prospectus Supplement, the Fifth Prospectus Supplement, the Sixth
Prospectus Supplement, the Seventh Prospectus Supplement, the Eighth Prospectus
Supplement, the Ninth Prospectus Supplement, the Tenth Prospectus Supplement,
the Eleventh Prospectus Supplement, the Twelfth Prospectus Supplement, the
Thirteenth Prospectus Supplement, the Fourteenth Prospectus Supplement, the
Fifteenth Prospectus Supplement, the Sixteenth Prospectus Supplement, the
Seventeenth Prospectus Supplement, the Eighteenth Prospectus Supplement, the
Nineteenth Prospectus Supplement, the Twentieth Prospectus Supplement, the
Twenty-First Prospectus Supplement, the Twenty-Second Prospectus Supplement, the
Twenty-Third Prospectus Supplement and the Twenty-Fourth Prospectus Supplement
and is qualified by reference to the Prospectus, the First Prospectus
Supplement, the Second Prospectus Supplement, the Third Prospectus Supplement,
the Fourth Prospectus Supplement, the Fifth Prospectus Supplement, the Sixth
Prospectus Supplement, the Seventh Prospectus Supplement, the Eighth Prospectus
Supplement, the Ninth Prospectus Supplement, the Tenth Prospectus Supplement,
the Eleventh Prospectus Supplement, the Twelfth Prospectus Supplement, the
Thirteenth Prospectus Supplement, the Fourteenth Prospectus Supplement, the
Fifteenth Prospectus Supplement, the Sixteenth Prospectus Supplement, the
Seventeenth Prospectus Supplement, the Eighteenth Prospectus Supplement, the
Nineteenth Prospectus Supplement, the Twentieth Prospectus Supplement, the
Twenty-First Prospectus Supplement, the
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Twenty-Second Prospectus Supplement, the Twenty-Third Prospectus Supplement and
the Twenty-Fourth Prospectus Supplement except to the extent that the
information herein contained supersedes the information contained in the
Prospectus, the First Prospectus Supplement, the Second Prospectus Supplement,
the Third Prospectus Supplement, the Fourth Prospectus Supplement, the Fifth
Prospectus Supplement, the Sixth Prospectus Supplement, the Seventh Prospectus
Supplement, the Eighth Prospectus Supplement, the Ninth Prospectus Supplement,
the Tenth Prospectus Supplement, the Eleventh Prospectus Supplement, the Twelfth
Prospectus, the Thirteenth Prospectus Supplement, the Fourteenth Prospectus
Supplement, the Fifteenth Prospectus Supplement, the Sixteenth Prospectus
Supplement, the Seventeenth Prospectus Supplement, the Eighteenth Prospectus
Supplement, the Nineteenth Prospectus Supplement, the Twentieth Prospectus
Supplement, the Twenty-First Prospectus Supplement, the Twenty-Second Prospectus
Supplement, the Twenty-Third Prospectus Supplement and the Twenty-Fourth
Prospectus Supplement. Capitalized terms used in this Twenty-Fifth Prospectus
Supplement and not otherwise defined herein have the meanings specified in the
Prospectus.
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THE DATE OF THIS TWENTY-FIFTH PROSPECTUS SUPPLEMENT IS
OCTOBER 19, 1999
SELLING STOCKHOLDERS
On October 19, 1999, of the Shares beneficially owned by Thomas C.K.
Yuen reflected in the Prospectus and the supplements thereto, 750 of which were
gifted to The UCI Foundation. The table of Selling Stockholders in the
Prospectus and the supplements thereto are hereby amended to reflect such gift
and supplemented to specifically include Shares received in such gift.
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