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EXCEL - IDEA: XBRL DOCUMENT - ASPEN TECHNOLOGY INC /DE/Financial_Report.xls
EX-32.1 - EX-32.1 - ASPEN TECHNOLOGY INC /DE/a2221018zex-32_1.htm
EX-31.2 - EX-31.2 - ASPEN TECHNOLOGY INC /DE/a2221018zex-31_2.htm
EX-10.29 - EX-10.29 - ASPEN TECHNOLOGY INC /DE/a2221018zex-10_29.htm
EX-31.1 - EX-31.1 - ASPEN TECHNOLOGY INC /DE/a2221018zex-31_1.htm
EX-23.1 - EX-23.1 - ASPEN TECHNOLOGY INC /DE/a2221018zex-23_1.htm
10-K - 10-K - ASPEN TECHNOLOGY INC /DE/a2221018z10-k.htm

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Exhibit 21.1

LIST OF SUBSIDIARIES OF ASPEN TECHNOLOGY, INC.

Name of Subsidiary
  State or Country
of Incorporation
1.   AspenTech Argentina S.R.L.    Argentina
2.   Aspen Technology Australia Pty. Ltd.    Australia
3.   Aspen Technology WLL   Bahrain
4.   AspenTech Europe S.A./N.V.    Belgium
5.   AspenTech Software Brazil Ltda.    Brazil
6.   AspenTech Canada Corporation   Canada
7.   Aspen Technology S.A.S.    Colombia
8.   Aspen Tech India Pte. Ltd.    India
9.   Aspen Technology S.r.l.    Italy
10.   AspenTech Japan Co. Ltd.    Japan
11.   AspenTech Solutions Sdn. Bhd.    Malaysia
12.   Aspen Tech de Mexico, S. de R.L. de C.V.    Mexico
13.   AspenTech Europe B.V.    Netherlands
14.   AspenTech (Beijing) Co., Ltd.    PRC
15.   AspenTech (Shanghai) Co., Ltd.    PRC
16.   Aspen Technology LLC   Russia
17.   AspenTech Pte. Ltd.    Singapore
18.   AspenTech Africa (Pty.) Ltd.    South Africa
19.   Aspen Technology S.L.    Spain
20.   AspenTech (Thailand) Ltd.    Thailand
21.   AspenTech Ltd.    UK
22.   Hyprotech UK Ltd.    UK
23.   AspenTech Canada Holdings, LLC   Delaware
24.   AspenTech Holding Corporation   Delaware
25.   Aspen Technology (Asia) Inc.    Delaware
26.   Aspen Technology International, Inc.    Delaware
27.   Aspen Technology Services Corporation   Delaware
28.   AspenTech Software Corporation   Delaware
29.   AspenTech Venezuela, C.A.    Venezuela
30.   SolidSim Engineering GmbH   Germany



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LIST OF SUBSIDIARIES OF ASPEN TECHNOLOGY, INC.