Dassault Systèmes Confirms Media Report Concerning a Trade Secret Violation by Siemens PLM Software GmbH 

Suresnes, France, September 3, 2008

Dassault Systèmes (DS) (Nasdaq: DASTY; Euronext Paris: #13065, DSY.PA), a world leader in 3D and Product Lifecycle Management (PLM) solutions, today confirmed a media report concerning a trade secret violation by Siemens Product Lifecycle Management Software (DE) GmbH, a competitor of Dassault Systemes.

On June 4, 2008 an article of the Frankfurter Allgemeine Zeitung (FAZ) reported that a violation by Siemens PLM of Dassault Systèmes trade secrets (including a specific customer list) had occurred.

After investigation, Siemens admitted having found a list of 3216 customer names from Germany, Switzerland and Austria, as mentioned by the FAZ article. Siemens did not provide any explanations regarding how such trade secret was made available to Siemens PLM, nor how this sensitive information had been exploited, despite its presence on their intranet.

The specific customer list was returned to Dassault Systèmes by Siemens with the assurance that any copy thereof would be destroyed. Siemens further committed to respect Dassault Systèmes trade secrets.

An internal audit conducted by Dassault Systèmes demonstrated that the above information was properly protected, and therefore Dassault Systèmes deeply regrets that information obtained illegally could be found on a competitor’s intranet, and reserves the right to any action it deems appropriate to enforce its rights.

 About Dassault Systèmes  

 As a world leader in 3D and Product Lifecycle Management (PLM) solutions, Dassault Systèmes brings value to more than 100,000 customers in 80 countries. A pioneer in the 3D software market since 1981, Dassault Systèmes develops and markets PLM application software and services that support industrial processes and provide a 3D vision of the entire lifecycle of products from conception to maintenance. The Dassault Systèmes portfolio consists of CATIA for designing the virtual product - SolidWorks for 3D mechanical design - DELMIA for virtual production - SIMULIA for virtual testing - ENOVIA for global collaborative lifecycle management, and 3DVIA for online 3D lifelike experiences. Dassault Systèmes is listed on the Nasdaq (DASTY) and Euronext Paris (#13065, DSY.PA) stock exchanges. For more information, visit http://www.3ds.com

CATIA, DELMIA, ENOVIA, SIMULIA, SolidWorks and 3D VIA are registered trademarks of Dassault Systèmes or its subsidiaries in the US and/or other countries.