The paper suggests a patent‐based methodology to study the implications of inbound and coupled open innovation adoption at the project level. The input–process–output–outcome model suggested in this work allows the analysis of firms' R&D projects and can be considered as an approach to investigate how companies achieve specific outputs and outcomes starting from certain inputs and employing open innovation practices. The methodology is tested on a sample of 35,857 patents of 214 worldwide companies from three top R&D spending industries. Results show that the model is able to delineate high performing applications of open innovation. Inbound open innovation is associated with exploitation activities and produces incremental or architectural innovation, with high innovation performance in terms of technological and market success. Coupled open innovation is linked to explorative behaviours aiming at getting radical innovation, but with a limited likelihood of the technology developed to be successful, at least in the short term.