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Filed Pursuant to Rule 424(b)(3)
Registration No. 333-57895
PROSPECTUS SUPPLEMENT
DATED SEPTEMBER 30, 1998
(To Prospectus dated June 26, 1998)
ADAPTEC, INC.
1,241,538 Shares of Common Stock
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This Prospectus Supplement, together with the Prospectus listed above, is
to be used by certain holders of the above-referenced securities or by their
transferees, pledgees, donees or their successors in connection with the offer
and sale of the above referenced securities.
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SELLING SECURITYHOLDERS
The table captioned "Selling Securityholders" commencing on pages 9 and 10
of the Prospectus is hereby amended to reflect the distribution from Silicon
Venture Partners, LLC of its 217,967 shares of Adaptec, Inc. common stock to the
individuals/entities listed below on this page 2 of this Supplement.
<TABLE>
<CAPTION>
NUMBER OF SHARES OF
COMMON STOCK BENEFICIALLY
OWNED AND OFFERED
SELLING SECURITYHOLDERS HEREBY
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<S> <C>
Thomas Armstrong................................................ 4,024
C. William Carey................................................. 6,036
Dr. James Considine.............................................. 6,036
Donald Creamer................................................... 6,036
Gerald E. Davidson Irrevocable Trust............................. 6,036
R. Ernest Ferrell Charitable Remainder Unitrust.................. 8,048
Charles Fuller................................................... 4,024
Shirley Hallberg................................................. 6,036
W. Hardy & Eleanor Hendren....................................... 6,036
Anita Howe-Waxman................................................ 8,048
Judith Isroff.................................................... 6,036
Dr. Lawrence & Janet Kaplan...................................... 4,024
Robert Levine IRA................................................ 4,024
101507 Canada.................................................... 6,036
Karl Matthies.................................................... 8,048
Tom & Ann McNamara............................................... 4,024
Glenn Oclassen Charitable Remainder Unitrust..................... 6,036
Dr. Stephen O'Connor............................................. 6,036
Michael Ohanian.................................................. 6,036
David Paradise................................................... 6,036
Jeffrey Parker Charitable Remainder Unitrust..................... 8,048
Jeffrey Parker Family Limited Partnership........................ 8,048
Douglas Percy.................................................... 4,024
Darvin Schanley.................................................. 4,024
Barry Scheur..................................................... 6,036
Joseph Sullivan.................................................. 6,036
TFA Lp........................................................... 8,048
Arnold Thompson.................................................. 6,036
Betty Thompson................................................... 4,024
LNY LLC.......................................................... 8,048
Michael Doyle.................................................... 80
Karen Gerrior.................................................... 160
Robert Katz...................................................... 482
Tom LaHaise...................................................... 160
Elisabeth & Mary Reynolds........................................ 80
Isabel & Eric Scharmer........................................... 160
Abby Marr........................................................ 321
Jessica Bain..................................................... 160
Newbury Street International LLC................................ 37,296
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217,967
</TABLE>
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