<PAGE>
Filed Pursuant to Rule 424(b)(3)
Registration No. 333-39101
PROSPECTUS SUPPLEMENT DATED APRIL 20, 1999
(To Prospectus dated October 30, 1997, as supplemented March 6, 1998, June
15, 1998, September 1, 1998, October 29, 1998, January 15, 1999 and April 14,
1999)
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
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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 successors in connection with the offer and sale of
the above referenced securities.
<PAGE>
The section entitled "Selling Securityholders" commencing on page 34 of the
Prospectus is hereby amended to include the following as an addition to the
information already presented therein:
SELLING SECURITYHOLDERS
<TABLE>
<CAPTION>
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NUMBER OF SHARES OF
PRINCIPAL AMOUNT OF NOTES COMMON STOCK BENEFICIALLY
BENEFICIALLY OWNED AND OWNED AND OFFERED
SELLING SECURITYHOLDER OFFERED HEREBY HEREBY (1)(2)
- ------------------------------------------------------------------------------------------------------
<S> <C> <C>
McMahan Securities Company, L.P. (3)........ $1,100,000 23,404
</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.
