<PAGE>
PROSPECTUS SUPPLEMENT DATED OCTOBER 29, 1998
(To Prospectus dated October 30, 1997)
CYMER, INC.
U.S. $172,500,000
3-1/2%/7-1/4% Step-Up Convertible Subordinated Notes due August 6, 2004
and
Shares of Common Stock Issuable Upon Conversion Thereof
---------------------------------
This Prospectus 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 succcessors in connection with the offer and sale
of the above referenced securities.
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The section entitled "Selling Securityholders" commencing on page 34 of the
Prospectus is hereby amended to include the following table:
<TABLE>
<CAPTION>
SELLING SECURITYHOLDERS
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NUMBER OF SHARES
PRINCIPAL AMOUNT OF COMMON STOCK
OF NOTES BENEFICIALLY
SELLING SECURITYHOLDER BENEFICIALLY OWNED OWNED AND OFFERED
AND OFFERED HEREBY HEREBY (1)(2)
- -----------------------------------------------------------------------------------
<S> <C> <C>
TQA Leverage Fund, L.P.. . . . . . . . 1,300,000 27,659
Argent Classic Convertible Arbitrage
Fund (Bermuda) (L.P.)(3) . . . . . . . 6,900,000 146,808
SAFECO Income Fund . . . . . . . . . . 8,000,000 170,212
</TABLE>
(1) Includes shares of Common Stock issuable upon conversion of the Notes.
(2) Assumes a conversion price of $47.00 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 of Notes."
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) Represents additional Notes and Shares being registered by the Selling
Securityholder.
