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                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549
 
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                                 SCHEDULE 14D-9
                               (AMENDMENT NO. 35)
 
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               Solicitation/Recommendation Statement Pursuant to
            Section 14(d)(4) of the Securities Exchange Act of 1934
 
                         QUICKTURN DESIGN SYSTEMS, INC.
                           (Name of Subject Company)
 
                         QUICKTURN DESIGN SYSTEMS, INC.
                      (Name of Person(s) Filing Statement)
 
                    COMMON STOCK, PAR VALUE $.001 PER SHARE
           (including the associated preferred stock purchase rights)
                         (Title of Class of Securities)
 
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                                   74838E102
                     (CUSIP Number of Class of Securities)
 
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                                 KEITH R. LOBO
                     PRESIDENT AND CHIEF EXECUTIVE OFFICER
                         QUICKTURN DESIGN SYSTEMS, INC.
                               55 W. TRIMBLE ROAD
                           SAN JOSE, CALIFORNIA 95131
                                 (408) 914-6000
      (Name, address and telephone number of person authorized to receive
       notice and communications on behalf of person(s) filing statement)
 
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                                    COPY TO:
 
                             LARRY W. SONSINI, ESQ.
                        WILSON SONSINI GOODRICH & ROSATI
                               650 PAGE MILL ROAD
                        PALO ALTO, CALIFORNIA 94304-1050
                                 (650) 493-9300
 
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                                 INTRODUCTION
 
  The Solicitation/Recommendation Statement on Schedule 14D-9 (the "Schedule
14D-9") originally filed on August 24, 1998, by Quickturn Design Systems,
Inc., a Delaware corporation (the "Company" or "Quickturn"), relates to an
offer by MGZ Corp., a Delaware corporation ("MGZ") and a wholly owned
subsidiary of Mentor Graphics Corporation, an Oregon corporation ("Mentor"),
to purchase the outstanding shares of the common stock, par value $.001 per
share (including the associated preferred stock purchase rights), of the
Company. All capitalized terms used herein without definition have the
respective meanings set forth in the Schedule 14D-9.
 
ITEM 8. ADDITIONAL INFORMATION TO BE FURNISHED
 
  The response to Item 8 is hereby amended by adding the following to the end
of the section entitled "Litigation Concerning the Offer":
 
  On January 7, 1999, Mentor and MGZ filed an application for a Temporary
Restraining Order in the Court of Chancery of the State of Delaware seeking to
enjoin the January 8, 1999 Special Meeting of Stockholders which had been
called by Mentor. On January 7, 1999, the Court of Chancery denied Mentor's
Application. On January 8, 1999, the Company issued a press release announcing
the decision. A copy of the press release is filed as Exhibit 73 hereto and is
incorporated herein by reference.
 
  On January 8, 1999, Mentor and MGZ filed a Motion for a Temporary
Restraining Order in the United States District Court for the District of
Delaware seeking to enjoin the January 8, 1999 Special Meeting of Stockholders
which had been called by Mentor. On January 8, 1999, the District Court denied
Mentor's Motion. A copy of the Company's press release announcing the decision
is filed as Exhibit 74 hereto and is incorporated herein by reference.
 
  The response to Item 8 is hereby amended further by adding the following to
the end of the section entitled "Proxy Solicitation":
 
  On January 8, 1999, Mentor announced that it was terminating its tender
offer, proxy solicitation and its proposal to acquire the Company, and was
withdrawing its call for the January 8, 1999 Special Meeting of Stockholders.
A copy of the Company's press release relating to Mentor's announcement is
filed as Exhibit 75 hereto and is incorporated herein by reference.
 
ITEM 9. MATERIAL TO BE FILED AS EXHIBITS
 
  The response to Item 9 is hereby amended by the addition of the following
new exhibits:
 

           
   Exhibit 73 Press release of the Company dated January 8, 1999.
   Exhibit 74 Press release of the Company dated January 8, 1999.
   Exhibit 75 Press release of the Company dated January 8, 1999.

 
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                                   SIGNATURE
 
  After reasonable inquiry and to the best of its knowledge and belief, the
undersigned certifies that the information set forth in this statement is
true, complete and correct.
 

                                          
 Dated: January 8, 1999                      QUICKTURN DESIGN SYSTEMS, INC.

 
                                              /s/ Keith R. Lobo
                                          By: _________________________________
                                              Keith R. Lobo
                                              President and Chief Executive
                                               Officer
 
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