After being made, a technical rule related to a geographic protection creates a kind of institution. This one is not neutral about the development, the technical choices, innovation and economic petiormances of firms to which it is applied. This paper deals with the interaction between technical rule and firms profitability. It follows three parts : 1) Using theoretic tools from other works (Marty F., 1998), firms are defined and characterised by a type of rationality and an efficiency level, 2) technical rule is defined by its interaction and consistency about each type of rationality, 3) the interaction between technical rule and real firms is studied : the dynamic and profitability creation possibilities are cleared. After this analysis phase, a conclusion is worked out : negotiations, constructions and application of technical rule is never a red fire or a simple norm. Even about the petiormances and direct utilisation by the firm, phenomena are complex. We just can try to understand and advise professionals. For each production area, some conclusions and perspectives are drawn and purposed to local firms.