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                                                                    EXHIBIT 99.5

                                                                       EXHIBIT A

NEITHER THESE SECURITIES NOR THE SECURITIES FOR WHICH THESE SECURITIES ARE
EXERCISABLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR
THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN
AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT AND IN COMPLIANCE WITH APPLICABLE STATE
SECURITIES OR BLUE SKY LAWS. NOTWITHSTANDING THE FOREGOING, THESE SECURITIES AND
THE SECURITIES ISSUABLE UPON EXERCISE OF THESE SECURITIES MAY BE PLEDGED IN
CONNECTION WITH A BONA FIDE MARGIN ACCOUNT OR OTHER LOAN OR FINANCING
ARRANGEMENT SECURED BY SUCH SECURITIES.

Warrant No. WD - ___                                  Number of Shares: ________
                                                         (subject to adjustment)

Date of Issuance: ___________, 2003

Original Issue Date (as defined in
 subsection 2(a)(i)(B)): __________, 2003

                             ASPEN TECHNOLOGY, INC.

                          COMMON STOCK PURCHASE WARRANT

                          (Void after _________, 2010)

     Aspen Technology, Inc., a Delaware corporation (the "Company"), for
value received, hereby certifies that ___________________, or its registered
assigns (the "Registered Holder"), is entitled, subject to the terms and
conditions set forth below, to purchase from the Company, at any time or from
time to time on or after the date of issuance and on or before 5:00 p.m.
(Eastern time) on ___________, 2010, __________(1) shares of Common Stock,
$0.10 par value per share, of the Company ("Common Stock"), at a purchase
price of $9.99(2) per share. The shares purchasable upon exercise of this
Warrant, and the purchase price per share, each as adjusted from time to time
pursuant to the provisions of this Warrant, are hereinafter referred to as
the "Warrant Shares" and the "Purchase Price," respectively.

     1.   EXERCISE

          (a)  EXERCISE FOR CASH. The Registered Holder may, at its option,
     elect to exercise this Warrant, in whole or in part and at any time or from
     time to time, by surrendering this Warrant, with the purchase form appended
     hereto as EXHIBIT I duly executed by or on behalf of the Registered Holder,
     at the principal office of the Company, or at such other office or agency
     as the Company may designate, accompanied by payment in full, in lawful
     money of the United States, of the Purchase Price payable in respect of the
     number of Warrant Shares purchased upon such exercise.

          (b)  CASHLESS EXERCISE

- ----------

(1)  Warrants will be issued for an aggregate of 2,002,002 shares, assuming
     stockholder approval of the one-for-three reverse stock split approved
     by the Board of Directors on June 1, 2003.

(2)  Assuming stockholder approval of the one-for-three reverse stock split
     approved by the Board of Directors on June 1, 2003.


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               (i)    The Registered Holder may, at its option, elect to
          exercise this Warrant, in whole or in part from time to time, on a
          cashless basis, by surrendering this Warrant, with the purchase form
          appended hereto as EXHIBIT I duly executed by or on behalf of the
          Registered Holder, at the principal office of the Company, or at such
          other office or agency as the Company may designate, by canceling a
          portion of this Warrant in payment of the Purchase Price payable in
          respect of the number of Warrant Shares purchased upon such exercise,
          PROVIDED that the Registered Holder may not elect to exercise this
          Warrant on a cashless basis to purchase shares of Common Stock that
          are the subject of (and may be freely resold under) a then-effective
          registration statement under the Securities Act of 1933, as amended
          (the "Act"). In the event of an exercise pursuant to this subsection
          1(b), the number of Warrant Shares issued to the Registered Holder
          shall be determined according to the following formula:

                                   X = Y(A-B)
                                       ------
                                         A

          Where:      X  =  the number of Warrant Shares that shall be issued
                            to the Registered Holder;

                      Y  =  the number of Warrant Shares for which this Warrant
                            is being exercised (which shall include both the
                            number of Warrant Shares issued to the Registered
                            Holder and the number of Warrant Shares subject to
                            the portion of the Warrant being cancelled in
                            payment of the Purchase Price);

                      A  =  the Fair Market Value (as defined below) of one
                            share of Common Stock; and

                      B  =  the Purchase Price then in effect.

               (ii)   The Fair Market Value per share of Common Stock shall be
          determined as follows:

                      (A)  If the Common Stock is listed on a national
               securities exchange, the Nasdaq National Market or another
               nationally recognized trading system as of the Exercise Date, the
               Fair Market Value per share of Common Stock shall be deemed to be
               the average of the high and low reported sale prices per share of
               Common Stock thereon on the trading day immediately preceding the
               Exercise Date, PROVIDED that if no such price is reported on such
               day, the Fair Market Value per share of Common Stock shall be
               determined pursuant to clause (B) below.

                      (B)  If the Common Stock is not listed on a national
               securities exchange, the Nasdaq National Market or another
               nationally recognized trading system as of the Exercise Date, the
               Fair Market Value per share of Common Stock shall be deemed to be
               the amount most recently determined by the Board of Directors of
               the Company to represent the fair market value per share of the
               Common Stock (including a determination for purposes of granting
               Common Stock options or issuing Common Stock under any plan,
               agreement or arrangement with employees of the Company); and,
               upon request of the Registered Holder, such Board (or a
               representative thereof) shall, as promptly as reasonably
               practicable but in any event not later than 20 days after such
               request, notify the Registered Holder of the Fair Market Value
               per share of Common Stock and furnish the Registered Holder with
               reasonable documentation of such Board's determination of such
               Fair Market Value. Notwithstanding the foregoing, if the Board
               has not made such a determination within the three-month period
               prior to the Exercise Date, then (a) the Board shall make, and
               shall provide or cause to be provided to the Registered Holder
               notice of, a determination of the Fair Market Value per share of
               the

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               Common Stock within 15 days of a request by the Registered Holder
               that it do so, and (b) the exercise of this Warrant pursuant to
               this subsection 1(b) shall be delayed until such determination is
               made and notice thereof is provided to the Registered Holder.

          (c)  EXERCISE DATE. Each exercise of this Warrant shall be deemed to
     have been effected immediately prior to the close of business on the day on
     which this Warrant shall have been surrendered to the Company as provided
     in subsection 1(a) or 1(b) above (the "Exercise Date"). At such time, the
     person or persons in whose name or names any certificates for Warrant
     Shares shall be issuable upon such exercise as provided in subsection 1(d)
     below shall be deemed to have become the holder or holders of record of the
     Warrant Shares represented by such certificates. The Company shall use all
     commercially reasonable efforts to deliver Warrant Shares hereunder
     electronically through the Depository Trust Corporation or another
     established clearing corporation performing similar functions.

          (d)  ISSUANCE OF CERTIFICATES. As soon as practicable after the
     exercise of this Warrant in whole or in part, and in any event within three
     Trading Days (as defined below) thereafter, the Company, at its expense,
     shall cause to be issued in the name of, and delivered to, the Registered
     Holder, or as the Registered Holder (upon payment by the Registered Holder
     of any applicable transfer taxes) may direct:

               (i)    a certificate or certificates for the number of full
                      Warrant Shares to which the Registered Holder shall be
                      entitled upon such exercise plus, in lieu of any
                      fractional share to which the Registered Holder would
                      otherwise be entitled, cash in an amount determined
                      pursuant to Section 3 below; and

               (ii)   in case such exercise is in part only, a new warrant or
                      warrants of like tenor, calling in the aggregate on the
                      face or faces thereof for the number of Warrant Shares
                      equal (without giving effect to any adjustment therein) to
                      the number of such shares called for on the face of this
                      Warrant minus the number of Warrant Shares for which this
                      Warrant was so exercised.

     For purposes of this Warrant, "Trading Day" shall mean (a) any day on which
     the Common Stock is listed on the Nasdaq National Market or another
     nationally recognized trading system on which the Common Stock is then
     listed or quoted or (b) if the Common Stock is not then listed or quoted on
     the Nasdaq National Market or another nationally recognized trading system,
     then a day on which trading occurs on the New York Stock Exchange (or any
     successor thereto).

     2.   ADJUSTMENTS

          (a)  ADJUSTMENTS TO PURCHASE PRICE FOR DILUTING ISSUES

               (i)    SPECIAL DEFINITIONS. For purposes of this Section 2, the
          following definitions shall apply:

                      (A)  "OPTION" shall mean rights, options or warrants to
               subscribe for, purchase or otherwise acquire Common Stock or
               Convertible Securities.

                      (B)  "ORIGINAL ISSUE DATE" shall mean the date on which
               this Warrant was first issued (or, if this Warrant was issued
               upon partial exercise of, or in replacement of, another warrant
               of like tenor, then the date on which such original warrant was
               first issued).

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                      (C)  "CONVERTIBLE SECURITIES" shall mean any evidences of
               indebtedness, shares or other securities directly or indirectly
               convertible into or exchangeable for Common Stock, but excluding
               Options.

                      (D)  "ADDITIONAL SHARES OF COMMON STOCK" shall mean all
               shares of Common Stock issued (or, pursuant to subsection
               2(a)(iii) below, deemed to be issued) by the Company after the
               Original Issue Date, other than shares of Common Stock issued,
               issuable or deemed issued:

                           (I)   as a dividend or distribution on Series D-1
                                 Convertible Preferred Stock or Series D-2
                                 Convertible Preferred Stock of the Company;

                           (II)  by reason of a dividend, stock split, split-up
                                 or other distribution on shares of Common Stock
                                 that is covered by subsection 2(b) or 2(c)
                                 below;

                           (III) to employees or directors of, or consultants
                                 to, the Company or any of its subsidiaries
                                 pursuant to a plan, agreement or arrangement
                                 approved by the Board of Directors of the
                                 Company and by a majority of the directors of
                                 the Company who are eligible to serve on the
                                 Audit Committee of such Board under the
                                 then-applicable rules of the Securities and
                                 Exchange Commission and the Nasdaq National
                                 Market (or such other trading or quotation
                                 facility on which the Common Stock is then
                                 listed);

                           (IV)  to Accenture LLP pursuant to agreements in
                                 effect on June 1, 2003; or

                           (V)   in connection with any transaction with any
                                 strategic investor, vendor or customer, lessor,
                                 customer, supplier, marketing partner,
                                 developer or integrator or any similar
                                 arrangement, in each case the primary purpose
                                 of which is not to raise equity capital,
                                 PROVIDED such issuance is approved by the Board
                                 of Directors of the Company and by a majority
                                 of the directors of the Company who are
                                 eligible to serve on the Audit Committee of
                                 such Board under the then-applicable rules of
                                 the Securities and Exchange Commission and the
                                 Nasdaq National Market (or such other trading
                                 or quotation facility on which the Common Stock
                                 is then listed).

               (ii)   NO ADJUSTMENT OF PURCHASE PRICE. No adjustment of the
          Purchase Price shall be made as the result of the issuance of
          Additional Shares of Common Stock if the consideration per share
          (determined pursuant to subsection 2(a)(v)) for such Additional Share
          of Common Stock issued or deemed to be issued by the Company is equal
          to or greater than the Purchase Price in effect immediately prior to
          the issuance or deemed issuance of such Additional Shares of Common
          Stock.

               (iii)  ISSUE OF SECURITIES TO BE A DEEMED ISSUE OF ADDITIONAL
          SHARES OF COMMON STOCK

                      (A)  If the Company at any time or from time to time after
               the Original Issue Date shall issue any Options or Convertible
               Securities (excluding Options or Convertible Securities which,
               upon exercise, conversion or exchange thereof, would entitle the
               holder thereof to receive shares of Common Stock that are
               specifically excepted from the definition of Additional Shares of
               Common Stock by subsection 2(a)(i)(D) above) or shall fix a
               record date for the determination of holders of any class of
               securities entitled to

                                       -4-
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               receive any such Options or Convertible Securities, then the
               maximum number of shares of Common Stock (as set forth in the
               instrument relating thereto without regard to any provision
               contained therein for a subsequent adjustment of such number)
               issuable upon the exercise of such Options or, in the case of
               Convertible Securities and Options therefor, the conversion or
               exchange of such Convertible Securities, shall be deemed to be
               Additional Shares of Common Stock issued as of the time of such
               issue or, in case such a record date shall have been fixed, as of
               the close of business on such record date.

                      (B)  If the terms of any Option or Convertible Security,
               the issuance of which resulted in an adjustment to the Purchase
               Price pursuant to the terms of subsection 2(a)(iv) below, are
               revised (either automatically pursuant the provisions contained
               therein or as a result of an amendment to such terms) to provide
               for either (1) any increase or decrease in the number of shares
               of Common Stock issuable upon the exercise, conversion or
               exchange of any such Option or Convertible Security or (2) any
               increase or decrease in the consideration payable to the Company
               upon such exercise, conversion or exchange, then, effective upon
               such increase or decrease becoming effective, the Purchase Price
               computed upon the original issue of such Option or Convertible
               Security (or upon the occurrence of a record date with respect
               thereto) shall be readjusted to such Purchase Price as would have
               obtained had such revised terms been in effect upon the original
               date of issuance of such Option or Convertible Security.
               Notwithstanding the foregoing, no adjustment pursuant to this
               clause (B) shall have the effect of increasing the Purchase Price
               to an amount which exceeds the lower of (i) the Purchase Price on
               the original adjustment date, or (ii) the Purchase Price that
               would have resulted from any issuances of Additional Shares of
               Common Stock between the original adjustment date and such
               readjustment date.

                      (C)  If the terms of any Option or Convertible Security
               (excluding Options or Convertible Securities which, upon
               exercise, conversion or exchange thereof, would entitle the
               holder thereof to receive shares of Common Stock which are
               specifically excepted from the definition of Additional Shares of
               Common Stock by subsection 2(a)(i)(D) above), the issuance of
               which did not result in an adjustment to the Purchase Price
               pursuant to the terms of subsection 2(a)(iv) below (either
               because the consideration per share (determined pursuant to
               subsection 2(a)(v) hereof) of the Additional Shares of Common
               Stock subject thereto was equal to or greater than the Purchase
               Price then in effect, or because such Option or Convertible
               Security was issued before the Original Issue Date), are revised
               after the Original Issue Date (either automatically pursuant the
               provisions contained therein or as a result of an amendment to
               such terms) to provide for either (1) any increase or decrease in
               the number of shares of Common Stock issuable upon the exercise,
               conversion or exchange of any such Option or Convertible Security
               or (2) any increase or decrease in the consideration payable to
               the Company upon such exercise, conversion or exchange, then such
               Option or Convertible Security, as so amended, and the Additional
               Shares of Common Stock subject thereto (determined in the manner
               provided in subsection 2(a)(iii)(A) above) shall be deemed to
               have been issued effective upon such increase or decrease
               becoming effective.

                      (D)  Upon the expiration or termination of any unexercised
               Option or unconverted or unexchanged (as applicable) Convertible
               Security which resulted (either upon its original issuance or
               upon a revision of its terms) in an adjustment to the Purchase
               Price pursuant to the terms of subsection 2(a)(iv) below, the
               Purchase Price shall be readjusted to such Purchase Price as
               would have obtained had such Option or Convertible Security never
               been issued.

                                       -5-
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                      (E)  No adjustment in the Purchase Price shall be made
               upon the issue of shares of Common Stock or Convertible
               Securities upon the exercise of Options or the issue of shares of
               Common Stock upon the conversion or exchange of Convertible
               Securities.

               (iv)   ADJUSTMENT OF PURCHASE PRICE UPON ISSUANCE OF ADDITIONAL
          SHARES OF COMMON STOCK. In the event the Company shall at any time
          after the Original Issue Date issue Additional Shares of Common Stock
          (including Additional Shares of Common Stock deemed to be issued
          pursuant to subsection 2(a)(iii)), without consideration or for a
          consideration per share less than the Purchase Price in effect
          immediately prior to such issue, then the Purchase Price shall be
          reduced, concurrently with such issue, to a price (calculated to the
          nearest cent) determined by multiplying such Purchase Price by a
          fraction, (A) the numerator of which shall be (1) the number of shares
          of Common Stock outstanding immediately prior to such issue plus (2)
          the number of shares of Common Stock which the aggregate consideration
          received or to be received by the Company for the total number of
          Additional Shares of Common Stock so issued would purchase at such
          Purchase Price; and (B) the denominator of which shall be the number
          of shares of Common Stock outstanding immediately prior to such issue
          plus the number of such Additional Shares of Common Stock so issued;
          PROVIDED that (i) for the purpose of this subsection 2(a)(iv), all
          shares of Common Stock issuable upon conversion or exchange of shares
          of Series D Convertible Preferred Stock of the Company, Options or
          Convertible Securities outstanding immediately prior to such issue or
          upon exercise of such securities shall be deemed to be outstanding,
          and (ii) the number of shares of Common Stock deemed issuable upon
          conversion or exchange of such outstanding shares of Series D
          Convertible Preferred Stock, Options or Convertible Securities and
          upon the exercise of such outstanding securities shall be determined
          without giving effect to any adjustments to the conversion or exchange
          price or conversion or exchange rate of such securities or the
          exercise price or number of shares issuable upon exercise of such
          outstanding securities resulting from the issuance of Additional
          Shares of Common Stock that is the subject of this calculation.

               (v)    DETERMINATION OF CONSIDERATION. For purposes of this
          subsection 2(a), the consideration received by the Company for the
          issue of any Additional Shares of Common Stock shall be computed as
          follows:

                      (A)  CASH AND PROPERTY. Such consideration shall:

                           (I)   insofar as it consists of cash, be computed at
                                 the aggregate of cash received by the Company,
                                 excluding amounts paid or payable for accrued
                                 interest;

                           (II)  insofar as it consists of property other than
                                 cash, be computed at the fair market value
                                 thereof at the time of such issue, as
                                 determined in good faith by the Board of
                                 Directors of the Company; and

                           (III) in the event Additional Shares of Common Stock
                                 are issued together with other shares or
                                 securities or other assets of the Company for
                                 consideration that covers both, be the
                                 proportion of such consideration so received,
                                 computed as provided in clauses (I) and (II)
                                 above, as determined in good faith by the Board
                                 of Directors of the Company.

                      (B)  OPTIONS AND CONVERTIBLE SECURITIES. The consideration
               per share received by the Company for Additional Shares of Common
               Stock deemed to have been issued pursuant to subsection
               2(a)(iii), relating to Options and Convertible Securities, shall
               be determined by dividing

                                       -6-
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                           (I)   the total amount, if any, received or
                                 receivable by the Company as consideration for
                                 the issue of such Options or Convertible
                                 Securities, plus the minimum aggregate amount
                                 of additional consideration (as set forth in
                                 the instruments relating thereto, without
                                 regard to any provision contained therein for a
                                 subsequent adjustment of such consideration)
                                 payable to the Company upon the exercise of
                                 such Options or the conversion or exchange of
                                 such Convertible Securities, or in the case of
                                 Options for Convertible Securities, the
                                 exercise of such Options for Convertible
                                 Securities and the conversion or exchange of
                                 such Convertible Securities, by

                           (II)  the maximum number of shares of Common Stock
                                 (as set forth in the instruments relating
                                 thereto, without regard to any provision
                                 contained therein for a subsequent adjustment
                                 of such number) issuable upon the exercise of
                                 such Options or the conversion or exchange of
                                 such Convertible Securities.

               (vi)   MULTIPLE CLOSING DATES. In the event the Company shall
          issue on more than one date Additional Shares of Common Stock which
          are comprised of shares of the same series or class of Preferred
          Stock, and such issuance dates occur within a period of no more than
          60 days, then, upon the final such issuance, the Purchase Price shall
          be readjusted to give effect to all such issuances as if they occurred
          on the date of the final such issuance (and without giving effect to
          any adjustments as a result of such prior issuances within such
          period).

          (b)  ADJUSTMENT FOR STOCK SPLITS AND COMBINATIONS. If the Company
     shall at any time or from time to time after the Original Issue Date effect
     a subdivision of the outstanding Common Stock, the Purchase Price then in
     effect immediately before that subdivision shall be proportionately
     decreased. If the Company shall at any time or from time to time after the
     Original Issue Date combine the outstanding shares of Common Stock, the
     Purchase Price then in effect immediately before the combination shall be
     proportionately increased. Any adjustment under this paragraph shall become
     effective at the close of business on the date the subdivision or
     combination becomes effective.

          (c)  ADJUSTMENT FOR CERTAIN DIVIDENDS AND DISTRIBUTIONS. In the event
     the Company at any time or from time to time after the Original Issue Date
     shall make or issue, or fix a record date for the determination of holders
     of Common Stock entitled to receive, a dividend or other distribution
     payable in additional shares of Common Stock, then and in each such event
     the Purchase Price in effect immediately before such event shall be
     decreased as of the time of such issuance or, in the event such a record
     date shall have been fixed, as of the close of business on such record
     date, by multiplying the Purchase Price then in effect by a fraction:

               (i)    the numerator of which shall be the total number of shares
                      of Common Stock issued and outstanding immediately prior
                      to the time of such issuance or the close of business on
                      such record date, and

               (ii)   the denominator of which shall be the total number of
                      shares of Common Stock issued and outstanding immediately
                      prior to the time of such issuance or the close of
                      business on such record date plus the number of shares of
                      Common Stock issuable in payment of such dividend or
                      distribution;

     PROVIDED, HOWEVER, that if such record date shall have been fixed and such
     dividend is not fully paid or if such distribution is not fully made on the
     date fixed therefor, the Purchase Price shall be recomputed accordingly as
     of the close of business on such record date and thereafter the Purchase

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     Price shall be adjusted pursuant to this paragraph as of the time of actual
     payment of such dividends or distributions.

          (d)  ADJUSTMENT IN NUMBER OF WARRANT SHARES. When any adjustment is
     required to be made in the Purchase Price pursuant to subsection 2(a), 2(b)
     or 2(c) above, the number of Warrant Shares purchasable upon the exercise
     of this Warrant shall be changed to the number determined by dividing (i)
     an amount equal to the number of shares issuable upon the exercise of this
     Warrant immediately prior to such adjustment, multiplied by the Purchase
     Price in effect immediately prior to such adjustment, by (ii) the Purchase
     Price in effect immediately after such adjustment.

          (e)  ADJUSTMENTS FOR OTHER DIVIDENDS AND DISTRIBUTIONS. In the event
     the Company at any time or from time to time after the Original Issue Date
     shall make or issue, or fix a record date for the determination of holders
     of Common Stock entitled to receive, a dividend or other distribution
     payable in securities of the Company (other than shares of Common Stock) or
     in cash or other property, then in each such event the Purchase Price in
     effect immediately prior to the record date fixed for determination of
     stockholders entitled to receive such dividend or distribution shall be
     reduced (effective on such record date) by the then fair market value of
     the distributed property distributed in respect of one outstanding share of
     Common Stock, as determined in good faith by the Company's Board of
     Directors. In such event, the Registered Holder, after receipt of the
     determination by the Company's Board of Directors, shall have the right to
     request that the Company select an appraiser (which shall be a nationally
     recognized investment banking firm or accounting firm), and the Registered
     Holder shall select an additional such appraiser and such fair market value
     shall be deemed to equal the average of the values determined by each of
     the of the appraisers. As an alternative to the foregoing adjustment to the
     Purchase Price, at the request of the Registered Holder delivered before
     the thirtieth day after such record date, provision shall be made so that
     the Registered Holder shall receive upon exercise hereof, in addition to
     the number of shares of Common Stock issuable hereunder, the kind and
     amount of securities of the Company, cash or other property that the
     Registered Holder would have been entitled to receive had this Warrant been
     exercised on the date of such event and had the Registered Holder
     thereafter, during the period from the date of such event to and including
     the Exercise Date, retained any such securities receivable during such
     period, giving application to all adjustments called for during such period
     under this Section 2 with respect to the rights of the Registered Holder.

          (f)  FUNDAMENTAL TRANSACTIONS. If, at any time while this Warrant is
     outstanding, (i) the Company effects any merger or consolidation of the
     Company with or into another Person, (ii) the Company effects any sale of
     all or substantially all of its assets in one or a series of related
     transactions, (iii) any tender offer or exchange offer (whether by the
     Company or another Person) is completed pursuant to which holders of Common
     Stock are permitted to tender or exchange their shares for other
     securities, cash or property, or (iv) the Company effects any
     reclassification of the Common Stock or any compulsory share exchange
     pursuant to which the Common Stock is effectively converted into or
     exchanged for other securities, cash or property (in any such case, a
     "Fundamental Transaction"), then the Holder shall have the right thereafter
     to receive, upon exercise of this Warrant, the same amount and kind of
     securities, cash or property as it would have been entitled to receive upon
     the occurrence of such Fundamental Transaction if it had been, immediately
     prior to such Fundamental Transaction, the holder of the number of Warrant
     Shares then issuable upon exercise in full of this Warrant (the "Alternate
     Consideration"). The aggregate Exercise Price for this Warrant will not be
     affected by any such Fundamental Transaction, but the Company shall
     apportion such aggregate Exercise Price among the Alternate Consideration
     in a reasonable manner reflecting the relative value of any different
     components of the Alternate Consideration. If holders of Common Stock are
     given any choice as to the securities, cash or property to be received in a
     Fundamental Transaction, then the Holder shall be given the same choice as
     to the Alternate

                                       -8-
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     Consideration it receives upon any exercise of this Warrant following such
     Fundamental Transaction.

          (g)  ROUNDING OF CALCULATIONS; MINIMUM ADJUSTMENTS. All calculations
     under this Section 2 shall be made to the nearest one tenth of a cent or
     the nearest 1/100th of a share, as applicable. The number of shares of
     Common Stock outstanding at any given time shall not include shares owned
     or held by or for the account of the Corporation, and the disposition of
     any such shares shall be considered an issue or sale of Common Stock.

          (h)  CERTIFICATE AS TO ADJUSTMENTS. Upon the occurrence of each
     adjustment pursuant to this Section 2, the Company at its expense will
     promptly compute such adjustment in accordance with the terms hereof and
     prepare a certificate describing in reasonable detail such adjustment and
     the transactions giving rise thereto, including all facts upon which such
     adjustment is based. Upon written request, the Company will promptly
     deliver a copy of each such certificate to the Registered Holder and to the
     Company's Transfer Agent. The Company shall, as promptly as reasonably
     practicable after the written request at any time of the Registered Holder
     (but in any event not later than 20 days thereafter), furnish or cause to
     be furnished to the Registered Holder a certificate setting forth (i) the
     Purchase Price then in effect and (ii) the number of shares of Common Stock
     and the amount, if any, of other securities, cash or property that then
     would be received upon the exercise of this Warrant.

     3.   FRACTIONAL SHARES. The Company shall not be required upon the exercise
of this Warrant to issue any fractional shares, but shall pay the value thereof
to the Registered Holder in cash on the basis of the Fair Market Value per share
of Common Stock, determined as follows:

          (a)  If the Common Stock is listed on a national securities exchange,
     the Nasdaq National Market or another nationally recognized trading system
     as of the Exercise Date, the Fair Market Value per share of Common Stock
     shall be deemed to be the average of the high and low reported sale prices
     per share of Common Stock thereon on the trading day immediately preceding
     the Exercise Date, PROVIDED that if no such price is reported on such day,
     the Fair Market Value per share of Common Stock shall be determined
     pursuant to clause (b) below.

          (b)  If the Common Stock is not listed on a national securities
     exchange, the Nasdaq National Market or another nationally recognized
     trading system as of the Exercise Date, the Fair Market Value per share of
     Common Stock shall be deemed to be the amount most recently determined by
     the Board of Directors of the Company to represent the fair market value
     per share of the Common Stock (including a determination for purposes of
     granting Common Stock options or issuing Common Stock under any plan,
     agreement or arrangement with employees of the Company); and, upon request
     of the Registered Holder, such Board (or a representative thereof) shall,
     as promptly as reasonably practicable but in any event not later than 20
     days after such request, notify the Registered Holder of the Fair Market
     Value per share of Common Stock and furnish the Registered

                                       -9-
<Page>

     Holder with reasonable documentation of such Board's determination of such
     Fair Market Value.

     4.   INVESTMENT REPRESENTATIONS. At the time of exercise of this Warrant,
the Registered Holder of this Warrant shall be required to represent and warrant
that that: (a) it is an "accredited investor" as defined in Rule 501(a) under
the Securities Act of 1933, as amended (the "Securities Act"); (b) it has made
such inquiry concerning the Company and its business and personnel as it has
deemed appropriate; (c) it has sufficient knowledge and experience in finance
and business that it is capable of evaluating the risks and merits of its
investment in the Company; and (d) if it is paying the Purchase Price in cash
pursuant to subsection 9(a), it is acquiring the shares of Common Stock by
exercise hereof for investment and not with a view to the resale or distribution
of such shares or any interest therein other than in a transaction that is
registered or exempt from registration under the Securities Act; provided that
such representation is without prejudice to the Registered Holder's right to
dispose of such shares of Common Stock in compliance with applicable securities
laws.

     5.   TRANSFERS, ETC.

          (a)  The Company shall maintain a register containing the name and
     address of the Registered Holder of this Warrant. The Registered Holder may
     change its address as shown on the warrant register by written notice to
     the Company requesting such change.

          (b)  Subject to the provisions of this Section 5 and the Investor
     Rights Agreement, this Warrant and all rights hereunder are transferable,
     in whole or in part, upon surrender of this Warrant with a properly
     executed assignment (in the form of EXHIBIT II hereto) at the principal
     office of the Company (or, if another office or agency has been designated
     by the Company for such purpose, then at such other office or agency).

      6.  NO IMPAIRMENT. The Company shall not, by amendment of its charter or
through any reorganization, transfer of assets, consolidation, merger,
dissolution, issue or sale of securities or any other voluntary action, avoid or
seek to avoid the observance or performance of any of the terms of this Warrant,
but shall at all times in good faith assist in the carrying out of all such
terms and in the taking of all such action as may be necessary or appropriate in
order to protect the rights of the Registered Holder against impairment. The
Company's obligations to issue and deliver Warrant Shares subject to and in
accordance with the terms hereof are absolute and unconditional, irrespective of
any action or inaction by the Registered Holder to enforce the same, any waiver
or consent with respect to any provision hereof, the recovery of any judgment
against any person or any action to enforce the same, or any setoff,
counterclaim, recoupment, limitation or termination, or any breach or alleged
breach by the Registered Holder or any other person of any obligation to the
Company or any violation or alleged violation of law by the Registered Holder or
any other person, and irrespective of any other circumstance which might
otherwise limit such obligation of the Company to the Registered Holder in
connection with the issuance of Warrant Shares. Nothing herein shall limit a
Registered Holder's right to pursue any other remedies available to it
hereunder, at law or in equity including a decree of specific performance and/or
injunctive relief with respect to the Company's failure to timely deliver
certificates representing shares of Common Stock upon exercise of this Warrant
as required pursuant to the terms hereof.

     7.   NOTICES OF RECORD DATE, ETC.  In the event:

          (a)  the Company shall take a record of the holders of its Common
               Stock (or other stock or securities at the time deliverable upon
               the exercise of this Warrant) for the purpose of entitling or
               enabling them to receive any dividend or other distribution, or
               to receive any right to subscribe for or purchase any shares of
               stock of any class or any other securities, or to receive any
               other right; or

                                      -10-
<Page>

          (b)  of any capital reorganization of the Company, any
               reclassification of the Common Stock of the Company, any
               consolidation or merger of the Company with or into another
               corporation (other than a consolidation or merger in which the
               Company is the surviving entity and its Common Stock is not
               converted into or exchanged for any other securities or
               property), or any transfer of all or substantially all of the
               assets of the Company; or

          (c)  of the voluntary or involuntary dissolution, liquidation or
               winding-up of the Company,

then, and in each such case, the Company will send or cause to be sent to the
Registered Holder a notice specifying, as the case may be, (i) the record date
for such dividend, distribution or right, and the amount and character of such
dividend, distribution or right, or (ii) the effective date on which such
reorganization, reclassification, consolidation, merger, transfer, dissolution,
liquidation or winding-up is to take place, and the time, if any is to be fixed,
as of which the holders of record of Common Stock (or such other stock or
securities at the time deliverable upon the exercise of this Warrant) shall be
entitled to exchange their shares of Common Stock (or such other stock or
securities) for securities or other property deliverable upon such
reorganization, reclassification, consolidation, merger, transfer, dissolution,
liquidation or winding-up. Such notice shall be sent at least 10 days prior to
the record date or effective date for the event specified in such notice.

     8.   CHARGES, TAXES AND EXPENSES. The Company shall pay any and all issue
and other similar taxes that may be payable in respect of any issuance or
delivery of shares of Common Stock upon exercise of this Warrant. The Company
shall not, however, be required to pay any tax that may be payable in respect of
any transfer involved in the issuance and delivery of Warrant Shares or Warrants
in a name other than that in which this Warrant is registered.

     9.   RESERVATION OF STOCK. The Company shall at all times reserve and keep
available, solely for issuance and delivery upon the exercise of this Warrant,
such number of Warrant Shares and other securities, cash and/or property, as
from time to time shall be issuable upon the exercise of this Warrant. If the
number of shares of Common Stock so reserved is insufficient, in addition to any
other remedy available to the Registered Holder, the Company shall take any
corporate action that is necessary to make available a sufficient number of
authorized but unissued and otherwise unreserved shares of Common Stock within
60 days after the occurrence of such deficiency.

     10.  EXCHANGE OR REPLACEMENT OF WARRANTS

          (a)  Upon the surrender by the Registered Holder, properly endorsed,
     to the Company at the principal office of the Company, the Company shall,
     subject to the provisions of Section 5 above, issue and deliver to or upon
     the order of the Registered Holder, at the Company's expense, a new Warrant
     or Warrants of like tenor, in the name of the Registered Holder or as the
     Registered Holder (upon payment by the Registered Holder of any applicable
     transfer taxes) may direct, calling in the aggregate on the face or faces
     thereof for the number of shares of Common Stock (or other securities, cash
     and/or property) then issuable upon exercise of this Warrant.

          (b)  Upon receipt of evidence reasonably satisfactory to the Company
     of the loss, theft, destruction or mutilation of this Warrant and (in the
     case of loss, theft or destruction) upon delivery of an indemnity agreement
     to the Company, or (in the case of mutilation) upon surrender and
     cancellation of this Warrant, the Company will issue, in lieu thereof, a
     new Warrant of like tenor.

     11.  LIMITATION ON EXERCISE. Notwithstanding anything to the contrary
contained herein, the number of shares of Common Stock that may be acquired by
the Registered Holder upon any exercise of this Warrant (or otherwise in respect
hereof) shall be limited to the extent necessary to ensure that, following such
exercise (or other issuance), the total number of shares of Common Stock then

                                      -11-
<Page>

beneficially owned by such Registered Holder and its affiliates and any other
individuals or entities whose beneficial ownership of Common Stock would be
aggregated with the Registered Holder's for purposes of Section 13(d) of the
Securities Exchange Act of 1934, as amended, does not exceed 4.999% (the
"Maximum Percentage") of the total number of issued and outstanding shares of
Common Stock (including for such purpose the shares of Common Stock issuable
upon such exercise). For such purposes, beneficial ownership shall be determined
in accordance with Section 13(d) of such Securities Exchange Act and the rules
and regulations promulgated thereunder. Each delivery of a notice of exercise of
this Warrant pursuant to Section 1 above will constitute a representation by the
Registered Holder that it has evaluated the limitation set forth in this
paragraph and determined that issuance of the full number of Warrant Shares
requested in such notice of Exercise is permitted under this paragraph. The
Company's obligation to issue shares of Common Stock in excess of the limitation
referred to in this Section 11 shall be suspended (and shall not terminate or
expire notwithstanding any contrary provisions hereof) until such time, if any,
as such shares of Common Stock may be issued in compliance with such limitation.
By written notice to the Company, the Registered Holder may waive the provisions
of this Section 11 or increase or decrease the Maximum Percentage to any other
percentage specified in such notice, but (a) any such waiver or increase will
not be effective until the sixty-first day after such notice is delivered to the
Company and (b) any such waiver or increase or decrease will apply only to the
Registered Holder and not to any other holder of warrants issued by the Company.

     12.  NOTICES. All notices and other communications from the Company to the
Registered Holder in connection herewith shall be mailed by certified or
registered mail, postage prepaid, or sent via a reputable nationwide overnight
courier service guaranteeing next business day delivery, to the address last
furnished to the Company in writing by the Registered Holder. All notices and
other communications from the Registered Holder to the Company in connection
herewith shall be mailed by certified or registered mail, postage prepaid, or
sent via a reputable nationwide overnight courier service guaranteeing next
business day delivery, to the Company at its principal office set forth below.
If the Company should at any time change the location of its principal office to
a place other than as set forth below, it shall give prompt written notice to
the Registered Holder and thereafter all references in this Warrant to the
location of its principal office at the particular time shall be as so specified
in such notice. All such notices and communications shall be deemed delivered
(a) two business days after being sent by certified or registered mail, return
receipt requested, postage prepaid, or (b) one business day after being sent via
a reputable nationwide overnight courier service guaranteeing next business day
delivery.

     13.  NO RIGHTS AS STOCKHOLDER. Until the exercise of this Warrant, the
Registered Holder shall not have or exercise any rights by virtue hereof as a
stockholder of the Company. Notwithstanding the foregoing, in the event (a) the
Company effects a split of the Common Stock by means of a stock dividend and the
Purchase Price of and the number of Warrant Shares are adjusted as of the date
of the distribution of the dividend (rather than as of the record date for such
dividend) and (b) the Registered Holder exercises this Warrant between the
record date and the distribution date for such stock dividend, the Registered
Holder shall be entitled to receive, on the distribution date, the stock
dividend with respect to the shares of Common Stock acquired upon such exercise,
notwithstanding the fact that such shares were not outstanding as of the close
of business on the record date for such stock dividend.

     14.  AMENDMENT. This Warrant may be amended only by a writing signed by
both the Company and the Registered Holder (or their respective successors or
assigns).

     15.  CONSTRUCTION. The section headings in this Warrant are for the
convenience of the parties and in no way alter, modify, amend, limit or restrict
the contractual obligations of the parties. The word "including" as used herein
shall not be construed so as to exclude any other thing not referred to or
described. In case any one or more of the provisions of this Warrant shall be
invalid or unenforceable in any respect, the validity and enforceability of the
remaining terms and provisions of this Warrant shall not

                                      -12-
<Page>

in any way be affected or impaired thereby and the parties will attempt in good
faith to agree upon a valid and enforceable provision which shall be a
commercially reasonable substitute therefor, and upon so agreeing, shall
incorporate such substitute provision in this Warrant.

     16.  GOVERNING LAW; WAIVER OF JURY TRIAL. All questions concerning the
construction, validity, enforcement and interpretation of this Warrant shall be
governed by and construed and enforced in accordance with the internal laws of
the State of Delaware. Each of the Company and the Registered Holder hereby
irrevocable submits to the exclusive jurisdiction of the state and federal
courts sitting in the State of Delaware, for the adjudication of any dispute
hereunder or in connection herewith or with any transaction contemplated hereby
or discussed herein (including with respect to the enforcement of any of the
transaction documents), and hereby irrevocably waives, and agrees not to assert
in any suit, action or proceeding, any claim that it is not personally subject
to the jurisdiction of any such court, or that such suit, action or proceeding
is improper. Each party hereby irrevocably waives personal service of process
and consents to process being served in any such suit, action or proceeding by
mailing a copy thereof via registered or certified mail or overnight delivery
(with evidence of delivery) to such party at the address in effect for notices
to it under this Warrant and agrees that such service shall constitute good and
sufficient service of process and notice thereof. Nothing contained herein shall
be deemed to limit in any way any right to serve process in any manner permitted
by law. Each of the Company and the Registered Holder hereby waives all rights
to a trial by jury.

     17.  FACSIMILE SIGNATURE.  This Warrant may be executed by facsimile
signature.

                                      -13-
<Page>

     EXECUTED as of the Date of Issuance indicated above.

                                            ASPEN TECHNOLOGY, INC.


                                            By:
                                               ---------------------------------
                                               Title:
                                                     ---------------------------
     ATTEST:


     --------------------------------
     Secretary

                                      -14-
<Page>

                                                                       EXHIBIT I

                                  PURCHASE FORM

To:  Aspen Technology, Inc.                                  Dated: ____________

     The undersigned is the Registered Holder of Warrant No. WD-____ (the
"Warrant") issued by Aspen Technology, Inc., a Delaware corporation (the
"Company"). Capitalized terms used herein and not otherwise defined have the
respective meanings set forth in the Warrant.

     a.   The Warrant is currently exercisable to purchase a total of
          ______________ Warrant Shares.

     b.   The undersigned Holder hereby exercises its right to purchase
          _________________ Warrant Shares pursuant to the Warrant.

     c.   The Holder intends that payment of the Purchase Price shall be made as
          (check one):

          ____    "Cash Exercise" under subsection 9(a)

          ____    "Cashless Exercise" under subsection 9(b)

     d.   If the holder has elected a Cash Exercise, the holder shall pay the
          sum of $____________ to the Company in accordance with the terms of
          the Warrant.

     e.   Pursuant to this exercise, the Company shall deliver to the holder
          _______________ Warrant Shares in accordance with the terms of the
          Warrant.

     Following this exercise, the Warrant shall be exercisable to purchase a
total of ____________ The undersigned represents and warrants to the Company
that: (a) it is an "accredited investor" as defined in Rule 501(a) under the
Securities Act of 1933, as amended (the "Securities Act"); (b) it has made such
inquiry concerning the Company and its business and personnel as it has deemed
appropriate; (c) it has sufficient knowledge and experience in finance and
business that it is capable of evaluating the risks and merits of its investment
in the Company; and (d) if it is paying the Purchase Price by "Cash Exercise"
pursuant to subsection 9(a), it is acquiring the shares of Common Stock by
exercise hereof for investment and not with a view to the resale or distribution
of such shares or any interest therein other than in a transaction that is
registered or exempt from registration under the Securities Act; provided that
such representation is without prejudice to the undersigned's right to dispose
of such shares of Common Stock in compliance with applicable securities laws.

Dated:                                  Name of Holder:
       ------------, ----

                                        (Print)
                                               ---------------------------------

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

                                        Name:
                                             -----------------------------------

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

                                        (SIGNATURE MUST CONFORM IN ALL RESPECTS
                                        TO NAME OF HOLDER AS SPECIFIED ON THE
                                        FACE OF THE WARRANT)

                                       I-1
<Page>

                                                                      EXHIBIT II

                                 ASSIGNMENT FORM

     FOR VALUE RECEIVED, _______________________________________ hereby sells,
assigns and transfers all of the rights of the undersigned under the attached
Warrant (No. ____) with respect to the number of shares of Common Stock of Aspen
Technology, Inc. covered thereby set forth below, unto:

NAME OF ASSIGNEE             ADDRESS                        NO. OF SHARES


Dated:                                  Signature:
      -----------------                           ------------------------------

                                      II-1