The aim of this paper is to explore open innovation (OI) implementation and its impact on firm innovation performance in sectors experiencing technological discontinuities. The paper employs the framework of inbound, outbound and coupled OI to identify processes reflecting sourcing, externalising and exchanging knowledge across organisational boundaries on upstream and downstream innovation activities and explores their impact on the innovation performance of new and established technology firms. The empirical setting is the UK bio‐pharmaceuticals sector during 1991 and 2001, a paradigmatic era of discontinous change and intensified OI implementation. First, our findings show that new technology firms (NTFs) and established technology firms (ETFs) differ in their extent and patterns of inbound, outbound and coupled OI, reflecting that they implement OI to manage their competences in light of technological change. Second, we identify a complex and multifaceted relationship between OI and patenting performance, with NTFs experiencing enhanced performance from some OI processes while ETFs experiencing challenges. The paper suggests that delineating OI into inbound, outbound and coupled, along upstream and downstream activities, offers a deeper understanding of the role of OI in innovation, guiding selective implementation in pursuing enhanced innovation performance during periods of discontinuous technological change.