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                        Quickturn Design Systems, Inc.
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CONTACTS:
        QUICKTURN DESIGN SYSTEMS, INC.          ABERNATHY MACGREGOR FRANK
        Joan Powell                             Pauline Yoshihashi
        Director, Marketing Communications      (213) 630-6550
        (408) 914-6701                          Matt Sherman
        joan@quickturn.com                      (212)371-5999

FOR IMMEDIATE RELEASE

             DELAWARE CHANCERY COURT TO ORDER DELAY OF ANY VOTE AT
                       MENTOR'S CHALLENGED MEETING DATE

                 LITIGATION WILL DETERMINE ACTUAL MEETING DATE

SAN JOSE, CALIF. -- OCTOBER 22, 1998 -- Quickturn Design Systems, Inc. (Nasdaq: 
QKTN) announced today that the Delaware Chancery Court will enter an order 
postponing until at least November 20, 1998 any vote to be taken at a special
stockholder meeting requested by Mentor Graphics Corporation. Mentor had
sought to have the vote proceed on October 29, 1998; however, in response to
Quickturn's motion to enjoin any vote on that date, Mentor consented to an
order postponing any vote.

The Quickturn Board of Directors continues to challenge the validity and 
legality of Mentor's attempt to call the special meeting as well as its ability 
to set the meeting date and record date of the special meeting. These matters 
continue to be the subject of litigation between Quickturn and Mentor. Subject 
to the resolution of this litigation, the Quickturn Board has set Friday, 
January 8, 1999 as the date for the special stockholder meeting, in accordance 
with the company's Bylaws.

On a separate matter, Quickturn announced today that the United States District 
court for the District of Delaware denied Mentor's motion for preliminary 
injunction as well as Quickturn's motion for preliminary injunction.

Quickturn Design Systems, Inc. is the leading provider of verification products 
and time-to-market engineering (TtME/TM/) services for the design of complex ICs
and electronic systems. The company's products are used worldwide by developers 
of high-performance computing, multimedia, graphics and communications systems. 
Quickturn is headquartered at 55 W. Trimble Road, San Jose, CA 95131-1013; 
Telephone: 408/914-6000. For more information, visit the Quickturn Web site at 
www.quickturn.com or send e-mail to info@quickturn.com.

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