Endogenous R&D symmetry in linear duopoly with one-way spillovers

A duopoly model of cost reducing R&D-Cournot market competition is extended to encompass endogenous timing of R&D investments. Under the assumption that R&D spillovers are zero under simultaneous choices of R&D and only flow from the R&D leader to the follower under sequential choices, sequential and simultaneous play at the R&D stage are compared in order to assess the role of technological externalities in stimulating or attenuating endogenous firm asymmetry. The only timing structure of the R&D stage sustainable as subgame–perfect Nash equilibrium involves simultaneous play and thus zero spillovers.