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                                QUICKTURN DESIGN SYSTEMS, INC.
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                (Name of Registrant as Specified In Its Charter)
 
                                 MENTOR GRAPHICS CORPORATION
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   MENTOR GRAPHICS EXPECTS THIRD QUARTER EARNINGS TO EXCEED ANALYST ESTIMATES
 
    Wilsonville, OR--October 12, 1998--Mentor Graphics Corporation (Nasdaq:
MENT) today announced that it expects to report earnings per share for the third
quarter ended September 30, 1998 20% above the consensus of analyst estimates,
or $0.12 per share. According to First Call, the current mean of analysts'
estimates for Mentor Graphics' third quarter is $0.10 per share. There will be
no special charges in the quarter. The Company is scheduled to report third
quarter results on October 29, 1998.
 
    Walden C. Rhines, President and CEO of Mentor Graphics, commented, "We are
pleased that our success in building our new product portfolio is flowing to the
bottom line. The results we expect to report for the third quarter reflect our
best gross margins in the 1990's, broad strength in North American software
sales, and a tripling of orders of our emulation products in Europe, as compared
to the same quarter a year ago. Combined with our focused expense controls and
with software product and emulation bookings up approximately 20% over the third
quarter of 1997, these anticipated results reflect Mentor's continued leadership
in the growing verification market. I'm looking forward to sharing more details
of our quarter in a few weeks."
 
               INFORMATION CONCERNING FORWARD-LOOKING STATEMENTS
 
    Certain statements contained in this press release, including, without
limitation, statements containing the words "believes," "expects," and words of
similar import, constitute "forward-looking" statements within the meaning of
Section 21E of the Securities Exchange Act of 1934, as amended. Such forward-
looking statements involve known and unknown risks, uncertainties and other
factors that may cause the actual results, performance or achievements of the
Company or industry results to be materially different from any future results,
performance or achievements expressed or implied by such forward-looking
statements. Prospective investors are cautioned not to place undue reliance on
such forward-looking statements. Mentor Graphics disclaims any obligation to
update any such factors or to publicly announce the results of any revisions to
any of the forward-looking statements contained herein to reflect future events
or developments.
 
    Mentor Graphics Corporation (NASDAQ: MENT) is a world leader in electronic
hardware and software design solutions, providing products and consulting
services for the world's largest electronics and semiconductor companies. The
company headquarters are located in Wilsonville, Oregon and it can be found on
the web at http://www.mentorg.com
 
For more information, contact:
 
Ryerson Schwark
Public Relations
503-685-1462
ry_schwark@mentorg.com
 
Dennis Weldon
Treasurer
503-685-1462
dennis_weldon@mentorg.com
 
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