After writing his thesis at the Université de Haute Alsace, France, under a CIFRE French Ministry of Research Training in Industry Convention with Saint-Gobain Recherche, Denis Klock joined Saint-Gobain Recherche in 1989 as a Research Engineer.

Transferred in 1992 to the Packaging Branch, he was appointed Manager of the R&D Laboratory of Saint-Gobain Desjonquères where he implemented a quality assurance policy. Then, in 1995, he was appointed Manager of Glass Elaboration for Saint-Gobain Desjonquères, a position in which he was able to develop innovative techniques, such as oxygen fusion.

In 2000, he was appointed Manager of the Glass-making Department for Saint-Gobain Vetri in Italy.
Since 2005, he is Manager of Glass Melting for Saint-Gobain Emballage in France.