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Filed Pursuant to Rule 424(b)(3)
Registration Statement No. 333-24557
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PROSPECTUS SUPPLEMENT DATED AUGUST 4, 1997
(To Prospectus dated June 24, 1997)
ADAPTEC, INC.
U.S. $230,000,000
4 3/4% Convertible Subordinated Notes due February 1, 2004
and
Shares of Common Stock Issuable Upon Conversion Thereof
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This Propsectus Supplement together, with the Prospectus, 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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The table captioned "Selling Securityholders" commencing on page 52 of
the Propsectus is hereby amended to reflect the following additions and changes.
<TABLE>
<CAPTION>
NUMBER OF SHARES OF
PRINCIPAL AMOUNT OF NOTES COMMON STOCK BENEFICIALLY
BENEFICIALLY OWNED OWNED AND OFFERED
SELLING SECURITYHOLDER AND OFFERED HEREBY HEREBY(1)(2)
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<S> <C> <C>
Merrill Lynch Pierce Fenner & Smith, Inc. .......................... 10,000,000 193,573
SBC Warburg, Inc. (3) ............................................. 6,000,000 116,144
Chase Securities Inc. .............................................. 6,000,000 116,144
State of Oregon/ Oregon Equity Fund ................................ 5,900,000 114,208
CFW-C, L.P. ....................................................... 4,000,000 77,429
Robertson Stephens & Co. L.L.P (4) ................................. 2,030,000 39,295
Lazard Freres & Co. LLC ............................................ 2,000,000 38,714
The Chase Manhattan Bank ttee for IBM Corporation Retirement
Plan Trust Dtd 12/18/45 ............................................ 4,055,000 78,493
Pension Reserves Investment Management Board ....................... 2,065,000 39,972
Bankers Trust ttee for Chrysler Corporation Employee #1 Pension Plan 2,355,000 45,586
State of Delaware Retirement ....................................... 1,350,000 26,132
State Street Bank Custodian for GE Pension Plan .................... 1,310,000 25,358
Arkansas PERS ...................................................... 1,550,000 30,003
ICI American Holdings Pension Trust ................................ 550,000 10,646
Zeneca Holdings Pension Trust ...................................... 550,000 10,646
Starvest Discretionary ............................................. 500,000 9,678
Southern Farm Bureau Life Insurance Co. ............................ 425,000 8,226
Franklin and Marshall College ...................................... 280,000 5,420
NALCO Chemical Co. Retirement Trust ................................ 225,000 4,355
Kapiolani Medical Center for Women and Children .................... 200,000 3,871
Island Insurance Convertible Account ............................... -- --
Retirement Plan for Pilots of Hawaiian Airlines .................... 150,000 2,903
Hawaii Airlines Employees Pension Plan - IAM ....................... 100,000 1,935
Hawaiian Airlines Pension Plan for Salaried Employees .............. 30,000 580
</TABLE>
(1) Includes shares of Common Stock issuable upon conversion of the Notes.
(2) Assumes a conversion price of $51.66 per share, and a cash payment in lieu
of any fractional share interest; such conversion price is subject to
adjustment as described under "Description of Notes -- Conversion."
Accordingly the number of shares of Common Stock issuable upon conversion
of the Notes may increase or decrease from time to time. Under the terms
of Indenture, fractional shares will not be issued upon conversion of the
Notes; cash will be paid in lieu of fractional shares, if any.
(3) Includes $3,000,000 principal amount of notes beneficially owned by Swiss
Bank Corporation for which SBC Warburg acts as investment advisor.
(4) Within the past three years, Robertson Stephens & Co., L.L.P. has acted as
an underwriter of securities of the Company.
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