Document:

<PAGE>

                                                                     EXHIBIT 4.5

                                RIGHTS AGREEMENT
                                 AMENDMENT NO. 2

     THIS AMENDMENT NO.2 TO RIGHTS AGREEMENT is entered into as of February 6,
2002 by Aspen Technology, Inc. (the "Company") and American Stock Transfer and
Trust Company, as Rights Agent (the "Rights Agent"), with respect to the Rights
Agreement dated as of March 12, 1998 between the Company and the Rights
Agreement, as amended to date (the "Rights Agreement").

     WHEREAS, no Distribution Date, as defined in Section 3(b) of the Rights
Agreement, has occurred; and

     WHEREAS, the Company has directed the Rights Agent to enter into this
Amendment No. 2 pursuant to Section 26 of the Rights Agreement;

     NOW, THEREFORE, in consideration of the premises and mutual agreements set
forth herein, the Company and the Rights Agent agree as follows:

     1.  The definition of "Acquiring Person" set forth in Section 1 of the
Rights Agreement is hereby deleted in its entirety and the following is
substituted in lieu thereof:

     "'Acquiring Person' shall mean any Person who or which, alone or together
with all Affiliates and Associates of such Person, shall be the Beneficial Owner
of Common Shares then outstanding that equals or exceeds such Person's Ownership
Threshold, but shall not include (A) the Company, any Subsidiary of the Company,
any employee benefit plan of the Company or of any of its Subsidiaries, or any
Person holding Common Shares for or pursuant to the terms of any such employee
benefit plan, (B) any such Person who or which has become such a Beneficial
Owner solely because (i) of a change in the aggregate number of Common Shares
outstanding since the last date on which such Person acquired Beneficial
Ownership of any Common Shares or (ii) it acquired such Beneficial Ownership in
the good faith belief that such acquisition would not cause such Beneficial
Ownership to exceed such Person's Ownership Threshold and such Person relied in
good faith in computing the percentage of its Beneficial Ownership on publicly
filed reports or documents of the Company which are inaccurate or out-of-date,
or (C) an Exempt Person. Notwithstanding clause (B) of the immediately preceding
sentence, if any Person that is not an Acquiring Person due to such clause (B)
does not reduce its percentage of Beneficial Ownership of Common Shares to an
amount less than such Person's Ownership Threshold by the Close of Business on
the fifth Business Day after notice from the Company (the date of notice being
the first day) that such Person's Beneficial Ownership of Common Shares so
exceeds such Person's Ownership Threshold, such Person shall, at the end of such
five Business Day period, become an Acquiring Person (and such clause (B) shall
no longer apply to such Person). For purposes of this definition, the
determination whether any Person acted in `good faith' shall be conclusively
determined by the Board of Directors of the Company."

<PAGE>

     2. The following definition shall be added to Section 1 of the Rights
Agreement:

     "'Exempt Person' shall mean Pine Ridge Financial Inc., Perseverance LLC and
Smithfield Fiduciary LLC (each a "Series B Investor"), unless and until such
time as such Series B Investor directly or indirectly become the Beneficial
Owner of Common Shares other than Common Shares received (i) as a dividend on,
or as a result of any conversion or redemption of, any shares of the Series B-1
Convertible Preferred Stock, $.10 par value per share, or Series B-2 Convertible
Preferred Stock, $.10 par value per share, of the Company, (ii) upon exercise of
warrants issued by the Company pursuant to the Securities Purchase Agreement,
dated as of the date hereof, between the Company and the Series B Investors, or
(iii) otherwise pursuant to such Securities Purchase Agreement or to the
Registration Rights Agreement, dated as of the date hereof, between the Company
and the Series B Investors. In addition, Exempt Person shall include any Person
to whom or which a Series B Investor transfers any shares of such Series B-1
Convertible Preferred Stock or Series B-2 Convertible Stock or any of such
warrants."

     IN WITNESS WHEREOF, the parties have duly executed this Amendment No. 2 as
of the date first written above.

ASPEN TECHNOLOGY, INC.

By: /s/ Lisa W. Zappala
  -------------------------------------
Name:   Lisa W. Zappala
Title:  Senior Vice President, Finance
        and Chief Financial Officer

AMERICAN STOCK TRANSFER & TRUST COMPANY, as Rights Agent

By: /s/ Herbert L. Lemmer
   ------------------------------------
Name:   Herbert L. Lemmer
Title:  Vice President<PAGE>
                                                                   EXHIBIT 10.30

[CABOT MICROELECTRONICS CORPORATION LOGO]

                              AMENDED AND RESTATED
                       CABOT MICROELECTRONICS CORPORATION
                           2000 EQUITY INCENTIVE PLAN

                          2001 DEPOSIT SHARE AGREEMENT

     THIS DEPOSIT SHARE AGREEMENT (the "Agreement") is made and entered into
this ______________ day of ______________, 2001, (the "Effective Date") by and
between Cabot Microelectronics Corporation (the "Company") and
__________________________ (the "Participant").

                              STATEMENT OF PURPOSE

     The Company has adopted the Amended and Restated Cabot Microelectronics
Corporation 2000 Equity Incentive Plan (the "Plan") for the benefit of its
eligible employees. The Participant is an employee of the Company who is
eligible to participate under the Plan, and who desires to participate in the
Plan pursuant to the terms and conditions of this Agreement, the Plan Restricted
Stock Agreement-2001 Deposit Share Award (the "Award Agreement"), and the Plan.

     NOW, THEREFORE, in consideration of the mutual covenants herein contained,
the Company and the Participant hereby agree as follows:

     1.   Election to Participate. The Participant hereby elects to participate
in the Plan by means of his/her execution of this Agreement.

     2.   Bonus Income. The Participant hereby elects to pay to the Company, via
personal check or other means acceptable to the Company on or by the Effective
Date, the following portion of his/her annual bonus amount that was paid to the
Participant on December 14, 2001:

<PAGE>

================================================================================

$                (the "Elected Bonus Amount").
---------------------------------------------

================================================================================

Any election made hereunder will be a one-time election and will not remain in
effect for subsequent annual bonus payments. The amount of election shall not be
less than $1,000.

     3.   Deposit Share Awards. The Company will convert the Elected Bonus
Amount to shares of Company common stock (the "Deposit Shares") issued to the
Participant under the Plan at the Fair Market Value of such stock on December
28, 2001, and will retain such shares subject to the terms of this Agreement,
the Award Agreement and the Plan. Such shares shall remain on deposit with the
Company through December 28, 2004 (the three year anniversary of December 28,
2001)(the "Distribution Date").

          On December 28, 2001, assuming Participant's satisfaction of the terms
of Section 2 of this Agreement, the Company will award to the Participant the
number of shares of Company common stock equal to fifty percent (50%) of the
number of Deposit Shares (the "Award Shares") pursuant to the terms and
restrictions of this Agreement, the Award Agreement and the Plan. Subject to the
terms of this Agreement, the Award Agreement and the Plan, the Deposit Shares
will be returned on the Distribution Date and the Participant's Award Shares
shall become fully transferable on such date, December 28, 2004, (the three year
anniversary of December 28, 2001) (the "Vesting Date"), assuming that the
Deposit Shares have remained on deposit with the Company through such date,
Participant remains an employee of the Company, and complies with the terms of
the Award Agreement and Plan. All Deposit Shares will be returned to the
Participant in the case of termination of employment.

     The Committee has the exclusive authority to elect to accelerate
distributions and vesting. Each Participant shall have the right to designate
one or more beneficiaries to receive a distribution in the event of the
Participant's death by filing with the Company a Beneficiary Designation Form.
The designated beneficiary or beneficiaries may be changed by a Participant at
any time prior to the Participant's death by the execution and delivery of a new
Beneficiary Designation Form. If no beneficiary has been designated, or if no
designated beneficiary survives the Participant, distributions will be made to
the Participant's estate.

                                      -2-
<PAGE>

     4.   Withdrawal of Deposit Shares. The Participant may request a Deposit
Share withdrawal at any time, however, such withdrawal prior to the Vesting Date
will result in the forfeiture of the Award Shares.

     5.   Incorporation of the Plan by Reference. The Plan, as it now exists and
as it may be amended hereafter, and the Award Agreement are incorporated herein
and made a part of this Agreement. When used herein, the terms which are defined
in the Plan shall have the meaning given them in the Plan. The Participant, or
if applicable the Participant's beneficiary, shall have the only right to
receive benefits determined in accordance with the Plan and this Agreement. The
Committee has the exclusive authority to interpret and apply the provisions of
the Plan, this Agreement, and the Award Agreement. Any interpretation of this
Agreement by the Committee and any decision made by it with respect to the
Agreement are final and binding on all persons. To the extent that there is any
conflict between the terms of this Agreement, the Award Agreement or the Plan,
the Plan shall govern. Capitalized terms used herein will have the same meaning
as under the Plan, unless stated otherwise.

     6.   Assignment and Alienation of Benefits. The right of each Participant
to any amount, benefit or payment hereunder will not, to the extent permitted by
law, be subject in any manner to attachment or other legal process for the debts
of that Participant; and no amount, benefit or payment will be subject to
anticipation, alienation, sale, transfer, assignment or encumbrance except by
will, by the laws of descent and distribution, or by a Participant election to
satisfy a property settlement agreement pursuant to a divorce.

     7.   Waiver of Priority The Participant hereby expressly waives any
priority he/she may have under any state or federal law with respect to any
claims he/she may have against the Company under the Plan beyond the rights
he/she would have as a general creditor of the Company.

     8.   Governing Law. This Agreement shall be construed under the laws of the
State of Illinois.

     IN WITNESS WHEREOF, the Company and the Participant have caused this
instrument to be executed as of the day and year first above written.

PARTICIPANT                             CABOT MICROELECTRONICS CORPORATION

                                        By:
---------------------------                 ------------------------------------

                                        Title:
                                               -------------------------

                                      -3-

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00033-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00033-of-00352.parquet"}]]