Luís Bettencourt, José Lobo, Deborah Strumsky, Hyejin Youn

Paper #: 14-06-020

Invention has been commonly conceptualized as a search over a space of com- binatorial possibilities. Despite the existence of a rich literature, spanning a variety of disciplines, elaborating on the recombinant nature of invention, we lack a formal and quantitative characterization of the combinatorial process underpinning inventive activity. Here we utilize U.S. patent records dating from 1790 to 2010 to formally characterize the invention as a combinatorial process. To do this we treat patented in- ventions as carriers of technologies and avail ourselves of the elaborate system of tech- nology codes used by the U.S. Patent Office to classify the technologies responsible for an invention’s novelty. We find that the combinatorial inventive process exhibits an invariant rate of “exploitation” (refinements of existing combinations of technologies) and “exploration” (the development of new technological combinations). This combi- natorial dynamic contrasts sharply with the creation of new technological capabilities – the building blocks to be combined – which has significantly slowed down. We also find that notwithstanding the very reduced rate at which new technologies are in- troduced, the generation of novel technological combinations engenders a practically infinite space of technological configurations.