After graduating, Jean-Marie Magnet began his professional career with Sogeti, a company for business management and information processing.
In 1978, he joined the IBSI (Intelligent Business System Informatique) group in Lyon. In 1983, he was promoted to Director of Operations for the North of France. Two years later, he moved to Paris and became Managing Director of the IBSI group.
In 1988, Jean-Marie Magnet acquired two subsidiaries of the IBSI group, IBSI Telecam specializing in security and networks and IBSI Automatismes et Systèmes specializing in industrial and technological IT.
Following these acquisitions, he founded the Ausy group, of which he is responsible.
On September 11, 2013, the Board of Directors of the Ausy group decided to separate the functions of Chairman of the Board of Directors and Chief Executive Officer. Jean-Marie Magnet cedes his function of Chief Executive Officer to Philippe Morsillo and remains Chairman of the Board of Directors.