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.