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EXHIBIT 5.1
HALE AND DORR LLP
COUNSELLORS AT LAW
60 STATE STREET, BOSTON, MASSACHUSETTS 02109
617-526-6000 o FAX 617-526-5000
October 10, 2000
Aspen Technology, Inc.
Ten Canal Park
Cambridge, Massachusetts 02141
REGISTRATION STATEMENT ON FORM S-3
Ladies and Gentlemen:
This opinion is furnished to you in connection with a Registration
Statement on Form S-3 (the "Registration Statement") to be filed with the
Securities and Exchange Commission under the Securities Act of 1933, as amended
(the "Securities Act"), for the registration of an aggregate of 660,276 shares
of Common Stock, $.10 par value per share (the "Shares"), of Aspen Technology,
Inc., a Delaware corporation (the "Company"). All of the Shares are being
registered on behalf of certain stockholders of the Company (the "Selling
Stockholders").
We are acting as counsel for the Company in connection with the
registration for resale of the Shares. We have examined signed copies of the
Registration Statement to be filed with the Commission. We have also examined
and relied upon minutes of meetings of the stockholders and the Board of
Directors of the Company as provided to us by the Company, stock record books of
the Company as provided to us by the Company, the Certificate of Incorporation
and By-Laws of the Company, each as restated and amended to date, and such other
documents as we have deemed necessary for purposes of rendering the opinions
hereinafter set forth.
In our examination of the foregoing documents, we have assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all documents submitted to
us as copies, the authenticity of the originals of such latter documents and the
legal competence of all signatories to such documents.
We assume that the appropriate action will be taken, prior to the offer and
sale of the Shares, to register and qualify the Shares for sale under all
applicable state securities or "blue sky" laws. We express no opinion herein as
to the laws of any state or jurisdiction other than the state laws of the
Commonwealth of Massachusetts, the General Corporation Law of the State of
Delaware and the federal laws of the United States of America.
Based upon and subject to the foregoing, we are of the opinion that the
Shares have been duly authorized and are validly issued, fully paid and
nonassessable.
It is understood that this opinion is to be used only in connection with
the offer and sale of the Shares while the Registration Statement is in effect.
Please note that we are opining only as to the matters expressly set forth
herein, and no opinion should be inferred as to any other matters. This opinion
is based upon currently existing statutes, rules, regulations and judicial
decisions, and we disclaim any obligation to advise you of any change in any of
these sources of law or subsequent legal or factual developments which might
affect any matters or opinions set forth herein.
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Aspen Technology, Inc.
October 10, 2000
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We hereby consent to the filing of this opinion with the Securities and
Exchange Commission as an exhibit to the Registration Statement in accordance
with the requirements of Item 601(b)(5) of Regulation S-K under the Securities
Act and to the use of our name therein and in the related prospectus under the
caption "Legal Matters." In giving such consent, we do not hereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities Act or the rules and regulations of the Securities and Exchange
Commission.
Very truly yours,
/s/ HALE AND DORR LLP
