Christine Defert is a director representing the employees, appointed to this position by the CFDT labor union. She has been Executive assistant within Dassault Systèmes' Industries organization since 2007. She has been a member of the Dassault Systèmes Works Council (CSE) in France and Deputy representative of the CSE at the board of directors from 2017 to 2024, as well as a member of the European Committee from 2020 to 2024. Before 2007, she served as office manager and executive assistant of several startups in France.

Christine Defert is a member of the executive committee of the CFDT union for metallurgy companies (Symetal) and, since 2023, a Labor court judge in France.