<PAGE>
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
------------------------
AMENDMENT NO. 25
TO SCHEDULE 14D-1
TENDER OFFER STATEMENT
(PURSUANT TO SECTION 14(D)(1) OF THE SECURITIES EXCHANGE ACT OF 1934)
QUICKTURN DESIGN SYSTEMS, INC.
(Name of Subject Company)
MENTOR GRAPHICS CORPORATION
MGZ CORP.
(Bidders)
COMMON STOCK, PAR VALUE $.001 PER SHARE
(including the Associated Rights)
(Title of Class of Securities)
74838E102
(CUSIP Number of Class of Securities)
------------------------
WALDEN C. RHINES
PRESIDENT AND CHIEF EXECUTIVE OFFICER
MENTOR GRAPHICS CORPORATION
8005 S.W. BOECKMAN ROAD
WILSONVILLE, OREGON 97070-7777
(503) 685-1200
(Name, Address and Telephone Number of Persons Authorized
to Receive Notices and Communications on Behalf of Bidders)
COPY TO:
JOHN J. HUBER, ESQ. CHRISTOPHER L. KAUFMAN, ESQ.
LATHAM & WATKINS LATHAM & WATKINS
1001 PENNSYLVANIA AVENUE, N.W. 75 WILLOW ROAD
WASHINGTON, DC 20004 MENLO PARK, CALIFORNIA 94025
(202) 637-2200 (650) 328-4600
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
<PAGE>
MGZ Corp., a Delaware corporation ("Purchaser"), and Mentor Graphics
Corporation, an Oregon corporation ("Parent"), hereby amend and supplement their
Tender Offer Statement on Schedule 14D-1 filed on August 12, 1998 (the
"Statement"), as amended, with respect to the offer by Purchaser to purchase all
outstanding shares of Common Stock, par value $.001 per share, of Quickturn
Design Systems, Inc., a Delaware corporation, for a purchase price of $12.125
per share, net to the seller in cash, without interest thereon, as set forth in
this Amendment No. 25. Capitalized terms used herein and not defined have the
meanings ascribed to them in the Statement.
ITEM 10. ADDITIONAL INFORMATION.
Item 10(f) of the Statement is hereby amended and supplemented by the
following:
1. On November 20, 1998, Parent and the Company entered into a Stipulation
regarding the Special Meeting, a copy of which is attached hereto as Exhibit
(a)(48) and is incorporated herein by reference.
2. On November 20, 1998, Parent issued a press release, a copy of which is
attached hereto as Exhibit (a)(49) and is incorporated herein by reference.
ITEM 11. MATERIAL TO BE FILED AS EXHIBITS.
(a)(48) Stipulation dated November 20, 1998.
(a)(49) Press Release dated November 20, 1998.
2
<PAGE>
SIGNATURES
After due inquiry and to the best of my knowledge and belief, I certify that
the information set forth in this statement is true, complete and correct.
<TABLE>
<S> <C> <C>
Dated: November 20, 1998 MENTOR GRAPHICS CORPORATION
By: /s/ GREGORY K. HINCKLEY
--------------------------------------
Name Gregory K. Hinckley
Title: Executive Vice President, Chief Operating
Officer and Chief Financial Officer
MGZ CORP.
By: /s/ GREGORY K. HINCKLEY
--------------------------------------
Name: Gregory K. Hinckley
Title: Secretary and Chief Financial Officer
</TABLE>
3
<PAGE>
IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE
IN AND FOR NEW CASTLE COUNTY
MENTOR GRAPHICS CORPORATION, )
an Oregon corporation, and MGZ CORP., a )
Delaware corporation, )
)
Petitioners, )
)
v. ) Civil Action No. 16584-NC
)
QUICKTURN DESIGN SYSTEMS, INC., )
a Delaware corporation, KEITH R. LOBO, )
GLEN M. ANTLE, RICHARD C. )
ALBERDING, MICHAEL R. D'AMOUR, )
YEN-SON (PAUL) HUANG, DR. DAVID )
K. LAM, WILLIAM A. HASLER, and )
CHARLES D. KISSNER, )
)
Respondents. )
STIPULATION AND ORDER
---------------------
WHEREAS, Mentor Graphics Corporation ("Mentor") asserts that it called a
special meeting of stockholders of Quickturn Design Systems, Inc. ("Quickturn")
for October 29, 1998 (the "Mentor Proposed Special Meeting");
WHEREAS, Quickturn asserts that the Mentor Proposed Special Meeting has not
been properly noticed by Mentor;
WHEREAS, Quickturn asserts that, if a special meeting was properly
requested, its board of directors properly scheduled a special meeting for
January 8, 1999 pursuant to Quickturn's bylaws (the "Quickturn Proposed Special
Meeting");
WHEREAS, Quickturn filed a motion for a preliminary injunction to enjoin
Mentor from proceeding with the Mentor Proposed Special Meeting on October 29,
1998 (the "Motion");
<PAGE>
WHEREAS, the Court conducted an expedited trial on October 19, 20, 23, 26
and 28, 1998 to determine the validity of the bylaw pursuant to which
Quickturn's board of directors asserts that it set the date for the Quickturn
Proposed Special Meeting;
WHEREAS, by letter dated November 17, 1998, the Court informed the parties
that it might be unable to decide the case and issue an opinion before November
24, 1998; and
WHEREAS, the parties wish to provide time for the Court to determine the
validity of the bylaw pursuant to which Quickturn's board of directors asserts
that it set the date for the Quickturn Proposed Special Meeting, for the Court
to issue its ruling, and for Quickturn and Mentor to communicate about the
ruling with Quickturn's stockholders;
IT IS HEREBY STIPULATED AND AGREED, by and between the parties hereto,
subject to the approval of the Court, as follows:
1. Subject to paragraph 4 herein, the Mentor Proposed Special Meeting
will be convened by a Mentor representative on November 24, 1998 at 11:00 a.m.,
at The Corporation Trust Company, 1209 Orange Street, Wilmington, Delaware
19801. The sole business conducted at the meeting will be to adjourn the
meeting immediately to December 11, 1998, at 11:00 a.m., at The Corporation
Trust Company, 1209 Orange Street, Wilmington, Delaware 19801.
2. All proxies held by Quickturn and its affiliates, and all shares of
Quickturn stock owned by Quickturn directors, shall not be present at the Mentor
Proposed Special Meeting on November 24, 1998. All proxies held by Mentor and
its affiliates, and all shares of Quickturn stock owned by Mentor, shall not be
present at the Mentor Proposed Special Meeting on November 24, 1998.
3. Other than the adjournment, there shall be no business conducted at
the Mentor Proposed Special Meeting on November 24, 1998. At the Mentor
Proposed Special Meeting on
-2-
<PAGE>
November 24, 1998, no stockholder vote shall be taken and no other action shall
be taken on any matter other than the adjournment of the meeting in accordance
with paragraph 1 of this Stipulation.
4. Except as expressly provided herein, this Stipulation does not affect
the substantive rights of any party. This Stipulation does not constitute or
reflect a ruling by the Court on any issue in this proceeding.
/s/ Thomas A. Beck
---------------------------------
Of Counsel: Kevin G. Abrams
Thomas A. Beck
Fredric J. Zepp Lisa A. Schmidt
Heidi Klein Catherine G. Dearlove
Latham & Watkins J. Travis Laster
505 Montgomery Street Thad J. Bracegirdle
San Francisco, CA 94111 Richards, Layton & Finger
(415) 391-0600 One Rodney Square
P. O. Box 551
Marc W. Rappel Wilmington, DE 19899
Latham & Watkins (302) 658-6541
633 West Fifth Street, Suite 4000 Attorneys for Plaintiffs
Los Angeles, CA 90071
(213) 485-1234
/s/ William M. Lafferty
---------------------------------
Of Counsel: Kenneth J. Nachbar
William M. Lafferty
James A. DiBiose Morris, Nichols, Arsht & Tunnell
David J. Berger 1201 North Market Street
Wilson Sonsini Goodrich & Rosati, PC P.O. Box 1347
650 Page Mill Road Wilmington, DE 19899
Palo Alto, CA 94304 (302) 658-9200
(650) 493-9300 Attorneys for Defendants
Dated: November 20, 1998
IT IS SO ORDERED. /s/ Jack B. Jacobs
---------------------------------
Vice Chancellor
Dated: November 20, 1998
-3-
<PAGE>
DELAWARE CHANCERY COURT ORDERS ADJOURNMENT UNTIL
DECEMBER 11 OF SPECIAL MEETING OF QUICKTURN
STOCKHOLDERS CALLED BY MENTOR
WILSONVILLE, OR, NOVEMBER 20, 1998 -- Mentor Graphics Corporation (Nasdaq: MENT)
announced today that the Delaware Chancery Court had ordered the adjournment
until December 11, 1998 of the special meeting of the stockholders of Quickturn
Design Systems (Nasdaq: QKTN), which had been called by Mentor for November 24,
1998.
The order to which both Mentor and Quickturn agreed arose from a letter from the
Delaware Chancery Court. The letter stated that it was not certain that the
Court would be able to decide Mentor's challenge to the validity of Quickturn's
poison pill and bylaw amendments prior to November 24, the date previously set
for the special meeting called by Mentor. The adjournment of the Quickturn
special meeting to December 11 is intended to provide time for the Court to
decide the case and for Mentor and Quickturn to communicate the ruling to
Quickturn's stockholders.
As previously announced, the principal purpose of the special meeting is to vote
on replacing the Quickturn Board of Directors with a slate of independent
directors nominated by Mentor. If the nominees are elected, Mentor expects
that, subject to their fiduciary duties to all Quickturn stockholders, the new
directors will take the steps necessary to facilitate the stockholders' ability
to accept Mentor 's $12.125 per share all-cash offer. Quickturn asserts that
the special meeting date has been conditionally set for January 8, 1999, citing
a bylaw purportedly adopted after Mentor commenced its offer, which bylaw is the
subject of the Delaware litigation.
Mentor's Offer to Purchase, proxy solicitation materials and related documents
are available on a Mentor World Wide Web site at http://www.mentorg.com/file.
The Dealer Manager for the Offer is Salomon Smith Barney. The Information Agent
for the Offer is MacKenzie Partners, Inc., which can be reached toll-free at
800-322-2885 or by collect call at 212-929-5500.
CONTACT: Anne M. Wagner Roy Winnick/Todd Fogarty
Vice President, Marketing Kekst and Company
503/685-1462 212/521-4800
# # #
