<PAGE>
Filed Pursuant to Rule 424(b)(3)
Registration No. 333-39101
PROSPECTUS SUPPLEMENT DATED APRIL 14, 1999
(To Prospectus dated October 30, 1997, as supplemented March 6, 1998, June 15,
1998, September 1, 1998, October 29, 1998 and January 15, 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
---------------------------------
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 of
PRINCIPAL AMOUNT OF NOTES Common Stock Beneficially
BENEFICIALLY OWNED AND Owned and Offered
SELLING SECURITYHOLDER OFFERED HEREBY Hereby (1)(2)
- -----------------------------------------------------------------------------------------------------------------------
<S> <C> <C>
Massachesetts Mutual Life Insurance Company. . . . . . . $3,000,000 63,829
MassMutual High Yield Partners II LLC. . . . . . . . . . $1,950,000 41,489
McMahon Securities Company, L.P. . . . . . . . . . . . . $ 100,000 2,127
FIST Franklin Convertible Securities Fund. . . . . . . . $4,250,000 90,425
</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.
