Equal treatment and socially optimal R&D in duopoly with one‐way spillovers

Abstract This paper examines the standard symmetric two‐period R&D model with a deterministic one‐way spillover structure: know‐how flows only from the high R&D firm to the low R&D firm (but not vice versa). Though firms are ex ante identical, one obtains a unique asymmetric equilibrium (pair) in R&D investments, leading to interfirm heterogeneity in the industry. R&D cooperation by means of a joint lab is considered and compared to the non cooperative solution. The main part of the paper provides a second‐best welfare analysis in which we show that the joint lab yields a socially optimal R&D level subject to an equal treatment (of firms) constraint, which also coincides with the noncooperative solution in the absence of spillovers. We also investigate the welfare costs of this equal treatment constraint and find that they can be quite significant.