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                                                                     Exhibit 4.5

                           [Form of Right Certificate]

Certificate No. [R]-
                       Rights

                  NOT EXERCISABLE AFTER DECEMBER 9, 2008, OR EARLIER IF REDEEMED
                  BY THE COMPANY. THE RIGHTS ARE SUBJECT TO REDEMPTION, AT THE
                  OPTION OF THE COMPANY, AT $.001 PER RIGHT, ON THE TERMS SET
                  FORTH IN THE RIGHTS AGREEMENT. RIGHTS BENEFICIALLY OWNED BY AN
                  ACQUIRING PERSON OR AN AFFILIATE OR ASSOCIATE OF AN ACQUIRING
                  PERSON (AS SUCH TERMS ARE DEFINED IN THE RIGHTS AGREEMENT) AND
                  BY ANY SUBSEQUENT HOLDER OF SUCH RIGHTS ARE NULL AND VOID AND
                  NONTRANSFERABLE.

                                Right Certificate

                              PRI AUTOMATION, INC.

         This certifies that _________________________, or registered assigns,
is the registered owner of the number of Rights set forth above, each of which
entitles the owner, thereof, subject to the terms, provisions and conditions of
the Rights Agreement dated as of December 9, 1998 (the "Rights Agreement"),
between PRI Automation, Inc., a Massachusetts corporation (the "Company"), and
State Street Bank and Trust Company, as Rights Agent (the "Rights Agent"),
unless the Rights evidenced hereby shall have been previously redeemed by the
Company, to purchase from the Company at any time after the Distribution Date
(as defined in the Rights Agreement) and prior to 5:00 p.m., Boston,
Massachusetts time, on the 10th anniversary of the date of the Rights Agreement
(the "Expiration Date"), at the office of the Rights Agent, or its successors as
Rights Agent, in Canton, Massachusetts, one one-hundred-thousandth (1/100,000th)
of a fully paid, nonassessable share of Class One Participating Cumulative
Preferred Stock, $.01 par value, of the Company (the "Preferred Shares"), at a
purchase price per one one-hundred-thousandth (1/100,000th) of a share equal to
$140 (the "Purchase Price") payable in cash, upon presentation and surrender of
this Right Certificate with the Form of Election to Purchase duly executed.

         The Purchase Price and the number and kind of shares which may be
purchased upon exercise of each Right evidenced by this Right Certificate, as
set forth above, are the Purchase Price and the number and kind of shares which
may be so purchased as of December 9, 1998. As provided in the Rights Agreement,
the Purchase Price and the number and kind of shares which may be purchased upon
the exercise of each Right evidenced by this Right Certificate are subject to
modification and adjustment upon the happening of certain events.

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         If the Rights evidenced by this Right Certificate are at any time
beneficially owned by an Acquiring Person or an Affiliate or Associate of an
Acquiring Person (as such terms are defined in the Rights Agreement), such
Rights shall be null and void and the holder of any such Right (including any
purported transferee or subsequent holder) shall not have any right to exercise
any such Right.

         This Right Certificate is subject to all the terms, provisions and
conditions of the Rights Agreement, which terms, provisions and conditions are
hereby incorporated herein by reference and made a part hereof and to which
reference to the Rights Agreement is hereby made for a full description of the
rights, limitations of rights, obligations, duties and immunities hereunder of
the Rights Agent, the Company and the holders of the Right Certificates. Copies
of the Rights Agreement are on file at the above-mentioned office of the Rights
Agent and are also available from the Company upon written request.

         This Right Certificate, with or without other Right Certificates, upon
surrender at the stock transfer or corporate trust office of the Rights Agent,
may be exchanged for another Right Certificate or Right Certificates of like
tenor and date evidencing Rights entitling the holder to purchase a like
aggregate number and kind of shares as the Rights evidenced by the Right
Certificate or Right Certificates surrendered shall entitle such holder to
purchase. If this Right Certificate shall be exercised in part, the holder shall
be entitled to receive upon surrender hereof another Right Certificate or Right
Certificates for the number of whole Rights not exercised.

         Subject to the provisions of the Rights Agreement, the Rights evidenced
by this Right Certificate may be redeemed by the Company at its option at a
redemption price (in cash or shares of Common Stock or other securities of the
Company deemed by the Board of Directors to be at least equivalent in value) of
$.001 per Right (which amount shall be subject to adjustment as provided in the
Rights Agreement) at any time prior to the earlier of (i) the Close of Business
on the day on which a Person has become an Acquiring Person or (ii) the
Expiration Date. Any of the provisions of the Rights Agreement (including,
without limitation, the date on which the Distribution Date shall occur, the
time during which the Rights may be redeemed or the terms of the Preferred
Shares) may be amended or supplemented, subject to the provision of the Rights
Agreement, prior to the Distribution Date without the approval of any holders of
the Rights.

         The Company may, but shall not be required to, issue fractions of
Preferred Shares or distribute certificates which evidence fractions of
Preferred Shares upon the exercise of any Right or Rights evidenced hereby. In
lieu of issuing fractional shares, the Company may elect to make a cash payment
as provided in the Rights Agreement for fractions of a share other than one
one-hundred-thousandth (1/100,000th) of a share or any integral multiple thereof
or to issue certificates or utilize a depository arrangement as provided in the
terms of the Rights Agreement and the Preferred Shares.

         No holder of this Right Certificate shall be entitled to vote or
receive dividends or be deemed for any purpose the holder of the Preferred
Shares or of any other securities of the Company which may at any time be
issuable on the exercise hereof, nor shall anything contained

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in the Rights Agreement or herein be construed to confer upon the holder hereof,
as such, any of the rights of a stockholder of the Company, including, without
limitation, any right to vote for the election of directors or upon any matter
submitted to stockholders at any meeting thereof, or to give or withhold consent
to any corporate action, or to receive notice of meetings or other actions
affecting stockholders (except as provided in the Rights Agreement), or to
receive dividends or other distributions or subscription rights, or otherwise,
until the Right or Rights evidenced by this Right Certificate shall have been
exercised as provided in accordance with the provisions of the Rights Agreement.






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         This Right Certificate shall not be valid or obligatory for any purpose
until it shall have been countersigned by the Rights Agent.

         WITNESS the facsimile signature of the proper officers of the Company
and its corporate seal.

Dated as of:

                                    PRI Automation, Inc.

                                    By:
                                       ----------------------------------------
                                               Authorized Signatory

Attest:

Authorized Signatory

Countersigned:

State Street Bank and Trust Company,
as Rights Agent

By:__________________________________
     Authorized Signatory

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                     [On Reverse Side of Right Certificate]

                          FORM OF ELECTION TO PURCHASE

(To be executed by the registered holder if such holder desires to exercise the
Rights represented by this Right Certificate.)

To the Rights Agent:

         The undersigned hereby irrevocably elects to exercise ____________
Rights represented by this Right Certificate to purchase the Preferred Shares
(or other shares) issuable upon the exercise of such Rights and requests that
certificates for such shares be issued in the name of:

Please insert social security
or other identifying number

                                           (Please print name and address)

         If such number of Rights shall not be all the Rights evidenced by this
Right Certificate, a new Right Certificate for the balance remaining of such
Rights shall be registered in the name of and delivered to:

Please insert social security
or other identifying number


(Please print name and address)

Dated:           , ____

                                                   Signature

Signature Guaranteed:
       NOTICE

         The signature on the foregoing Form of Election to Purchase must
correspond to the name as written upon the face of this Right Certificate in
every particular, without alteration or enlargement or any change whatsoever.

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