<PAGE>


                                                              FILED
                                                          DEC 19 1997
                                                        RICHARD W. WIERING
                                                    CLERK, U.S. DISTRICT COURT
                                                 NORTHERN DISTRICT OF CALIFORNIA
                                                             SAN JOSE



                 IN THE UNITED STATES DISTRICT COURT

                FOR THE NORTHERN DISTRICT OF CALIFORNIA

CADENCE DESIGN SYSTEMS, INC.,                         NO. C 95-20828 RMW(PVT)

       Plaintiff,                                      PRELIMINARY INJUNCTION

  v.

AVANT!, INC., et al.,

      Defendants.
---------------------------------

     Plaintiff's motion for a preliminary injunction pursuant to Federal Rule
of Civil Procedure 65 was heard on September 10, 1996 and on December 19,
1997 following the mandate issued by the Ninth Circuit with respect to the
court's order of March 18, 1997. The court has read all papers submitted both
before and after the hearing, listened to the oral argument of the parties,
considered the input of its technical expert and been guided by the Ninth
Circuit's opinion. The court incorporates its findings and conclusions from
the March 18, 1997 order as modified by the Ninth Circuit's opinion.

     IT IS HEREBY ORDERED THAT defendant Avant!, its officers, agents,
servants, employees and attorneys and any and all persons in active concert
with them who receive actual notice of this order, by personal service or
otherwise (collectively, "Avant!"), are hereby restrained





                                   1


<PAGE>

and enjoined, pending trial, from:

     1.  Infringing Cadence's copyrights in Cadence's Design Framework II
software product or directly or indirectly marketing, selling, leasing,
licensing, copying or transferring any product or work copied or derived from
Cadence's Design Framework II, specifically including, but not limited to,
Avant!'s ArcCell, ArcCellBV, and ArcCellXO products (collectively,
"ArcCell"); and

     2.  Possessing or using any copies, in any medium including printed
matter and electronic media, of any portion of the source code or object code
for ArcCell or any other product, to the extent that that portion is copied
or derived from Cadence's Design Framework II, and Avant! is further ordered
to return to Cadence any such copies under its possession or control by
January 30, 1998 provided, however, that Avant!'s counsel, and independent
experts working with them, may retain copies of said code solely for purposes
of this litigation.

     IT IS HEREBY FURTHER ORDERED THAT defendant Avant! is to forthwith
deliver by mail or otherwise a copy this Order to all current or former
purchasers, licensees, users or recipients of ArcCell or any product copied or
derived from Cadence's Design Framework II and obtain confirmation from them
as to whether they have a functioning copy of ArcCell or such product. Avant!
is to file under seal with the court by January 30, 1998 a list: (1)
identifying each such purchaser, licensee, user, or recipient; (2) whether
each has a functioning copy; and, if not, (3) when and how it became
non-functioning. Avant! is to require, to the extent it has a legal right to
do so, any such purchaser, licensee, user or recipient to return the ArcCell
or such other product to Avant! or destroy it. Avant! is to provide Cadence
by January 30, 1998 with a list of the names and addresses of any such
purchaser, licensee, user or recipient who still maintains a functional copy
of ArcCell or such other product and when it will become non-functional.

     This Order does not affect or in any way release Avant! from those
activities that were enjoined by this court's order of March 18, 1997. In the
March 18, 1997 order the court ordered Cadence to post a bond of $50,000 for
the payment of such damages as may be incurred or suffered by Avant! if it be
found that Avant! has been wrongfully enjoined or restrained. That bond shall

                                 2

<PAGE>

remain in effect but must be modified to ensure coverage of this current
Order.


DATED:  12/19/97
                                                /s/ Ronald M. Whyte
                                                -------------------------
                                                RONALD M. WHYTE
                                                United States District Judge






                                  3