Christine Defert is a director representing the employees, appointed to this position by the CFDT labor union. She has been Executive assistant of two vice presidents Industries of Dassault Systèmes 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.