Offensive - Economic model and natural experiment

Innovation rate is not the highest when first innovators have monopolistic control

Weighted means of annual rates of innovation by phase

	Monopoly	Entry	Balance	Shakeout	Mature
Rate of all innovations	0.39	0.57	0.62	0.36	0.43
Rate of major innovations	0.19	0.29	0.22	0.18	0.22
Rate of net firm entry	0.22	5.05	-0.07	-4.97	0.16

Source : M. Gort and S. Keppler - "Time paths in the diffusion of product innovation", The Economic Journal, v. 92, 1982

R&D spendings (with respect to sales) have decreased among largest patent holders

Source: NBER R&D Masterfile, Annual Reports.