The development of formal ICT standards is a loose form of collaborative innovation: firms first develop rival technologies, some of which are then eventually selected in the standard. Against this background, firms often use informal consortia to define a clearer technology roadmap ahead of the formal standard setting process. The paper aims to assess how such consortia influence the volume of patents filed around standards, and whether this is efficient. We show that their effect actually depends on the strength of firms' incentives to develop the standard. Consortium membership triggers a higher number of patent files when insufficient rewards for essential patents induce underinvestment in the standard. This effect is necessarily pro-efficient. In situations where excessive rewards induce patent races, consortium membership only moderately increases or even reduces their volume of patents. At least in the latter case, the effect of consortia membership is also pro-efficient.
