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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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                                   FORM 8-A/A

                                 AMENDMENT NO. 1

                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                    PURSUANT TO SECTION 12(b) OR 12(g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                             ASPEN TECHNOLOGY, INC.
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             (Exact name of registrant as specified in its charter)


                DELAWARE                                 04-2739697
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(State of incorporation or organization)    (I.R.S. employer identification no.)

TEN CANAL PARK, CAMBRIDGE, MASSACHUSETTS                              02141
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(Address of principal executive offices)                           (Zip code)

If this form relates to the               If this form relates to the
registration of a class of securities     registration of a class of securities
pursuant to Section 12(b) of the          pursuant to Section 12(g) of the
Exchange Act and is effective pursuant    Exchange Act and is effective pursuant
to General Instruction A.(c), check       to General Instruction A.(d), check
the following box. [ ]                    the following box. [X]

Securities Act registration statement number to which
this form relates:______________________________________________ (If applicable)

Securities to be registered pursuant to Section 12(b) of the Act:

Title of each class                               Name of each exchange on
to be so registered                         which each class is to be registered
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       NONE.

Securities to be registered pursuant to Section 12(g) of the Act:

                     COMMON STOCK, $.10 PAR VALUE PER SHARE
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                                (Title of Class)

         The undersigned registrant hereby amends the following items, exhibits
and portions of its registration statement on Form 8-A (dated as of 
September 13, 1994) as set forth in the pages attached hereto:

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ITEM 1.  DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED.

         On March 12, 1998, Aspen Technology, Inc., a Massachusetts corporation
("Aspen Massachusetts"), changed its state of incorporation by merging with and
into Aspen Technology, Inc., a Delaware corporation and wholly owned subsidiary
of Aspen Massachusetts (the "Company"). The Company's authorized capital stock
consists of 40,000,000 shares of Common Stock, $.10 par value per share, and
10,000,000 shares of Preferred Stock, $.10 par value per share.

COMMON STOCK

         Holders of Common Stock are entitled to one vote per share for each
share held of record on all matters submitted to a vote of stockholders and do
not have cumulative voting rights. Holders of a plurality of the shares of
Common Stock entitled to vote in any election of Directors may elect all of the
Directors in the class standing for election. Subject to preferential dividend
rights with respect to any outstanding Preferred Stock, holders of Common Stock
are entitled to receive ratably such dividends, if any, as may be declared by
the Board of Directors out of funds legally available therefor. Upon
liquidation, dissolution or winding up of the Company, holders of Common Stock
are entitled to share ratably in the assets of the Company legally available for
distribution to the holders of Common Stock, subject to any prior rights of any
outstanding Preferred Stock. Holders of Common Stock have no cumulative voting
rights nor any preemptive, subscription, redemption or conversion rights. All
outstanding shares of Common Stock are validly issued, fully paid and
non-assessable. The rights, preferences and privileges of holders of Common
Stock are subject to, and may be adversely affected by, the rights of the
holders of shares of any series of Preferred Stock which the Company may
designate and issue in the future.

PREFERRED STOCK

         The Board of Directors is authorized, subject to any limitations
prescribed by law, without further stockholder approval, to issue from time to
time up to an aggregate of 10,000,000 shares of Preferred Stock in one or more
series. Each such series of Preferred Stock shall have such number of shares,
designations, preferences, voting powers, qualifications and special or relative
rights or privileges, which may include, among others, dividend rights, voting
rights, redemption and sinking fund provisions, liquidation preferences and
conversion rights, as shall be determined by the Board of Directors in a
resolution or resolutions providing for the issuance of such series. Any such
series of Preferred Stock, if so determined by the Board of Directors, may have
full voting rights with the Common Stock or superior or limited voting rights,
and may be convertible into Common Stock or another security of the Company.

         The Company has granted the Board of Directors the authority to issue
Preferred Stock and to determine its rights and preferences in order to
eliminate delays associated with a stockholder vote on specific issuances. The
issuance of Preferred Stock, while providing desirable flexibility in connection
with possible acquisitions and other corporate purposes, could have the effect
of making it more difficult for a third party to acquire, or of discouraging a
third party from acquiring, a majority of the outstanding voting stock of the
Company. The Company has designated and reserved an aggregate of 400,000 shares
of authorized but unissued Preferred Stock for issuance as Series A
participating cumulative preferred stock, $.10 par value per share, of the
Company ("Series A Preferred Stock") pursuant to the Company's Stockholder
Rights Plan. See "-- Rights Plan."


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DELAWARE LAW AND CERTAIN CHARTER AND BY-LAW PROVISIONS

         The Company is subject to the provisions of Section 203 of the General
Corporation Law of Delaware. Section 203 prohibits a publicly-held Delaware
corporation from engaging in a "business combination" with an "interested
stockholder" for a period of three years after the date of the transaction in
which the person became an interested stockholder, unless the business
combination is approved in a prescribed manner. A "business combination"
includes mergers, asset sales and other transactions resulting in a financial
benefit to the interested stockholder. Subject to certain exceptions, an
"interested stockholder" is a person who, together with affiliates and
associates, owns, or within three years did own, 15% or more of the
corporation's outstanding voting stock.

         The Certificate of Incorporation of the Company provides for the
division of the Board of Directors into three classes as nearly equal in size as
possible with staggered three-year terms. In addition, the Certificate of
Incorporation provides that directors may be removed only for cause by the
affirmative vote of the holders of two-thirds of the shares of capital stock of
the corporation entitled to vote. Under the Certificate of Incorporation, any
vacancy on the Board of Directors, however occurring, including a vacancy
resulting from an enlargement of the Board, may only be filled by vote of a
majority of the directors then in office. The classification of the Board of
Directors and the limitations on the removal of directors and filling of
vacancies could have the effect of making it more difficult for a third party to
acquire, or of discouraging a third party from acquiring, control of the
Company.

         The Certificate of Incorporation also provides that any action required
or permitted to be taken by the stockholders of the Company at any annual
meeting or special meeting of stockholders may only be taken if it is properly
brought before such meeting and may not be taken by written consent in lieu of a
meeting. The Certificate of Incorporation further provides that special meetings
of the stockholders may only be called by the Chairman of the Board of
Directors, the Chief Executive Officer or, if none, the President of the Company
or by the Board of Directors. Under the Company's By-Laws, in order for any
matter to be considered properly brought before a meeting, a stockholder must
comply with certain requirements regarding advance notice to the Company. The
foregoing provisions could have the effect of delaying until the next
stockholders' meeting stockholder actions which are favored by the holders of a
majority of the outstanding voting securities of the Company. These provisions
may also discourage another person from making a tender offer for the Common
Stock, because such person, even if it acquired a majority of the outstanding
voting securities of the Company, would be able to take action as a stockholder
(such as electing new directors or approving a merger) only at a duly called
stockholders' meeting, and not by written consent.

         The General Corporation Law of Delaware provides generally that the
affirmative vote of a majority of the shares entitled to vote on any matter is
required to amend a corporation's certificate of incorporation or by-laws,
unless a corporation's certificate of incorporation or by-laws, as the case may
be, requires a greater percentage. The Company's Certificate of Incorporation
and By-Laws require the affirmative vote of the holders of at least 75% of the
shares of capital stock of the Company issued and outstanding and entitled to
vote to amend or repeal any of the provisions described in the prior two
paragraphs.

         The Certificate of Incorporation contains certain provisions permitted
under the General Corporation Law of Delaware relating to the liability of
directors. The provisions eliminate a director's liability for monetary damages
for a breach of fiduciary duty, except in certain circumstances involving
wrongful acts, such as the breach of a director's duty of loyalty or acts or
omissions which involve intentional misconduct or a knowing violation of law.
Further, the Certificate of Incorporation contains provisions to indemnify the
Company's directors and officers to the fullest extent permitted by the General
Corporation Law of



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Delaware. The Company believes that these provisions will assist the Company in
attracting and retaining qualified individuals to serve as directors and
officers.

RIGHTS PLAN

         On March 12, 1998, the Board of Directors of the Company adopted a
Stockholder Rights Agreement (the "Rights Plan") and distributed one Right for
each outstanding share of Common Stock. The Rights were issued to holders of
record of Common Stock outstanding on March 12, 1998. Each share of Common Stock
issued after March 12, 1998 will also include one Right, subject to certain
limitations. Each Right when it becomes exercisable will initially entitle the
registered holder to purchase from the Company one one-hundredth (1/100th) of a
share of Series A Preferred Stock at a price of $175.00 (the "Purchase Price").

         Currently the Rights are attached to outstanding shares of Common
Stock. The Rights are not now exercisable and cannot be transferred separately.
The Rights will become exercisable and separately transferable when the Company
learns that any person or group has acquired beneficial ownership of 15% or more
of the outstanding Common Stock or on such other date as may be designated by
the Board of Directors following the commencement of, or first public disclosure
of an intent to commence, a tender or exchange offer for outstanding Common
Stock that could result in the offeror becoming the beneficial owner of 15% or
more of the outstanding Common Stock. In such circumstances, holders of the
Rights will be entitled to purchase, for the Purchase Price, a number of
hundredths of a share of Series A Preferred Stock equivalent to the number of
shares of Common Stock (or, in certain circumstances, other equity securities)
having a market value of twice the Purchase Price. Beneficial holders of 15% or
more of the outstanding Common Stock, however, would not be entitled to exercise
their Rights in such circumstances. As a result, their voting and equity
interests in the Company would be substantially diluted if the Rights were to be
exercised.

         The Rights expire in March 2008, but may be redeemed earlier by the
Company at a price of $.01 per Right, in accordance with the provisions of the
Rights Plan.

TRANSFER AGENT AND REGISTRAR

     The transfer agent and registrar for the Common Stock is American Stock
Transfer & Trust Company.

         THE FOREGOING DESCRIPTION OF THE CAPITAL STOCK OF THE COMPANY DOES NOT
PURPORT TO BE COMPLETE AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO THE
COMPANY'S CERTIFICATE OF INCORPORATION, THE CERTIFICATE OF DESIGNATION OF SERIES
A PARTICIPATING CUMULATIVE PREFERRED STOCK, THE RIGHTS AGREEMENT AND THE FORM OF
RIGHT CERTIFICATE, EACH OF WHICH IS INCORPORATED HEREIN BY REFERENCE.




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ITEM 2.         EXHIBITS.

 *3.1      Certificate of Incorporation of Aspen Technology, Inc.

**3.1A     Certificate of Designation of Series A Participating Cumulative
           Preferred Stock of Aspen Technology, Inc.

 *3.2      By-Laws of Aspen Technology, Inc.

  4.0      Specimen certificate of Common Stock, $.10 par value per share

 *4.1      Rights Agreement dated as of March 12, 1998 between Aspen
           Technology, Inc. and American Stock Transfer and Trust Company, as
           Rights Agent

**4.3      Form of Right Certificate

*          Incorporated by reference to the corresponding Exhibit to the
           Registrant's Current Report on Form 8-K dated March 26, 1998.

**         Incorporated by reference to the corresponding Exhibit to the
           Registrant's Form 10-Q dated May 15, 1998.





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                                    SIGNATURE

         Pursuant to the requirements of Section 12 of the Securities Exchange
Act of 1934, the registrant has duly caused this registration statement to be
signed on its behalf by the undersigned, thereunto duly authorized.

                                      ASPEN TECHNOLOGY, INC.

Dated: June 10, 1998                   By:  /s/ Mary A. Palermo
                                          --------------------------------------
                                          Mary A. Palermo
                                          Executive Vice President, Finance and
                                          Chief Financial Officer
















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                                                                     EXHIBIT 4.0


[LOGO] NUMBER SHARES AZ ____ ASPEN TECHNOLOGY, INC. __________________ Incorporated under the laws of the State of Delaware COMMON STOCK SEE REVERSE FOR CERTAIN DEFINITIONS THIS CERTIFIES THAT CUSIP 045327 10 3 is the owner of FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK $.10 PAR VALUE OF Aspen Technology, Inc. transferable on the books of the corporation by such owner in person or by attorney upon surrender of this certificate duly endorsed or assigned. This certificate and the shares represented hereby are subject to the laws of the State of Delaware and to the Certificate of Incorporation and By-Laws of the corporation, as now in effect or hereafter amended. This certificate is not valid until countersigned and registered by the Transfer Agent and Registrar. WITNESS the facsimile seal of the corporation and the facsimile signatures of its duly authorized officers. Dated: [LOGO] /s/ Lawrence Evans /s/ Mary A. Palermo CHAIRMAN AND CHIEF EXECUTIVE OFFICER EXECUTIVE VICE PRESIDENT AND CHIEF FINANCIAL OFFICER
COUNTERSIGNED AND REGISTERED AMERICAN STOCK TRANSFER & TRUST COMPANY TRANSFER AGENT AND REGISTRAR By AUTHORIZED SIGNATURE 2
THE CORPORATION IS AUTHORIZED TO ISSUE MULTIPLE CLASSES AND SERIES OF STOCK. THE FULL TEXT OF THE POWERS, DESIGNATIONS, PREFERENCES AND RELATIVE, PARTICIPATING, OPTIONAL, OR OTHER SPECIAL RIGHTS OF EACH CLASS OF STOCK OR SERIES THEREOF AND THE QUALIFICATIONS, LIMITATIONS, OR RESTRICTIONS OF SUCH PREFERENCES AND/OR RIGHTS, ALL VESTING POWERS, QUALIFICATIONS AND SPECIAL AND RELATIVE RIGHTS OF THE SHARES OF EACH SUCH CLASS, AS SET FORTH IN THE CERTIFICATE OF INCORPORATION, WILL BE FURNISHED TO THE HOLDER HEREOF WITHOUT CHARGE, UPON WRITTEN REQUEST TO THE CORPORATION. The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations: TEN COM -- as tenants in common UNIF GIFT MIN ACT -- Custodian TEN ENT -- as tenants by the entirety --------- ---------- JT TEN -- as joint tenants with right (Cust) (Minor) of survivorship and not as under Uniform Gifts to Minors tenants in common Act _________________________ (State) Additional abbreviations may also be used though not in the above list. For value received, _______________ hereby sell, assign and transfer unto PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE __________________________________________ ______________________________________________________________________________________________________ ______________________________________________________________________________________________________ PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS INCLUDING POSTAL ZIP CODE OF ASSIGNEE ______________________________________________________________________________________________________ ______________________________________________________________________________________________________ ______________________________________________________________________________________________________ _______________________________________________________________________________________________ Shares of the common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint ______________________________________________________________________________________________________ ______________________________________________________________________________________________________ Attorney to transfer the said stock on the books of the within-named corporation with full power of substitution in the premises. Dated, ________________ _________________________________________ Signature(s) Guaranteed __________________________________________________ THE SIGNATURE(s) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15. This certificate also evidences and entitles the holder hereof to certain Rights as set forth in a Rights Agreement dated as of March 12, 1998, as it may be amended from time to time (the "Rights Agreement"), between Aspen Technology, Inc. (the "Company") and American Stock Transfer & Trust Company, as Rights Agent (the "Rights Agent"), the terms of which are hereby incorporated herein by reference and a copy of which is on file at the principal executive offices of the Company. Under certain circumstances, as set forth in the Rights Agreement, such Rights will be evidenced by separate certificates and will no longer be evidenced by this certificate. The Company will mail to the holder of this certificate a copy of the Rights Agreement without charge after receipt of a written request therefor. Rights beneficially owned by Acquiring Persons or their Affiliates or Associates (as such terms are defined in the Rights Agreement) and by any subsequent holder of such rights are null and void and nontransferable. NOTICE: The signature to this assignment must correspond with the name as written upon the face of the Certificate, in every particular, without alteration or enlargement, or any change whatever.