One of the key features of our economies consists of the coexistence of different technologies supplying similar products and services. Also, we often observe that an “old” technology is improved when a new one, doing basically the same things, appears. Behind this process of improvement of the old technology almost always lies an intentional research activity carried out by the owner of the old technology, whose aim is to delay as much as possible the loss of its market share. We focus our attention on this competition process and we supply a formal model capable of describing the delay of the overtaking of the new technology over the old one