| | | | | | | | | | | | | | |
| | | | | State or Country |
| | | Name of Subsidiary | | of Incorporation |
| 1 | | AGI Mexicana S.A. De C.V. | | Mexico |
| 2 | | Apex Optimisation SRO | | Czech Republic |
| 3 | | Apex Optimisation Technologies B.V. | | Netherlands |
| 4 | | Argent & Waugh Limited | | United Kingdom |
| 5 | | Aspen Paradigm Holding LLC | | Delaware |
| 6 | | Aspen Technology (Asia) Inc. | | Delaware |
| 7 | | Aspen Technology Australia Pty. Ltd. | | Australia |
| 8 | | Aspen Technology Holdings Corporation | | Delaware |
| 9 | | Aspen Technology International, Inc. | | Delaware |
| 10 | | Aspen Technology LLC | | Russia |
| 11 | | Aspen Technology Middle East Ltd. | | Saudi Arabia |
| 12 | | Aspen Technology S.A.S. | | Colombia |
| 13 | | Aspen Technology Quebec Inc. | | Canada |
| 14 | | Aspen Technology Regional Headquarters Company | | Saudi Arabia |
| 15 | | Aspen Technology S.L. | | Spain |
| 16 | | Aspen Technology Services Corporation | | Delaware |
| 17 | | AspenTech (Beijing) Ltd. | | PRC |
| 18 | | AspenTech (Shanghai) Ltd. | | PRC |
| 19 | | AspenTech (Thailand) Ltd. | | Thailand |
| 20 | | AspenTech Africa (Pty.) Ltd. | | South Africa |
| 21 | | AspenTech Argentina S.R.L. | | Argentina |
| 22 | | AspenTech Australia Holding Pty Ltd | | Australia |
| 23 | | AspenTech Canada Corporation | | Canada |
| 24 | | AspenTech Canada Holdings, LLC | | Delaware |
| 25 | | AspenTech Corporation | | Delaware |
| 26 | | AspenTech de Mexico S. de R.L. de C.V. | | Mexico |
| 27 | | AspenTech Europe B.V. | | Netherlands |
| 28 | | AspenTech Europe, S.A./N.V. | | Belgium |
| 29 | | AspenTech GmbH | | Germany |
| 30 | | AspenTech Holding Corporation | | Delaware |
| 31 | | AspenTech India Private Ltd. | | India |
| 32 | | AspenTech Japan Co. Ltd. | | Japan |
| 33 | | AspenTech Ltd. | | United Kingdom |
| 34 | | AspenTech Norway AS | | Norway |
| 35 | | AspenTech Pte. Ltd. | | Singapore |
| 36 | | AspenTech S.r.l. | | Italy |
| 37 | | AspenTech Software Brasil Ltda. | | Brazil |
| 38 | | AspenTech Software Corporation | | Delaware |
| 39 | | AspenTech Solutions Sdn. Bhd. | | Malaysia |
| 40 | | AspenTech Technologies Gulf LLC-OPC | | Abu Dhabi |
| 41 | | AspenTech SRL | | Romania |
| 42 | | AspenTech Venezuela C.A. | | Venezuela |
| 43 | | CAMO Smart Software Inc. | | New Jersey |