This article analyzes R&D policies when the returns to cost-reducing and demand-creating R&D are imperfectly appropriable and market structure is endogenous. We generalize previous characterizations of appropriability to permit the possibility that own and rival R&D are imperfect substitutes. We...

Using data from the Federal Trade Commission's Line of Business Program and survey measures of technological opportunity and appropriability conditions, this paper finds that overall firm size has a very small, statistically in- significant effect on business unit R & D intensity when either...