We investigate why and how knowledge transparency between competitors are needed for radical innovation. Previous scholars considered that coopetition (i.e. collaboration between competing firms) could not be a suitable strategy. Knowledge transparency invites opportunism. Thus, even for a radical innovation purpose, being highly transparent with a competitor is a fallacy. Our research goes beyond this specific approach of coopetition and reveals that firms can preserve transparency even if the partners behave opportunistically. We develop counter-intuitive propositions based on a conceptual discussion followed by insight from an extreme case study of two pharmaceutical competitors which managed to share their knowledge transparently and create a revolutionary drug (i.e. the Plavix). Our study mainly highlights that firms need to fight against the intuitive reaction of reducing transparency when the partner behaves opportunistically. Reducing the transparency inevitably leads to “shooting itself in the foot” because the reduction of transparency of one partner leads to the destruction of any possibility to create a radical innovation. Moreover, our research represents interesting guidelines for top managers by : (1) confirming that coopetition strategies are relevant in addressing the challenges of radical innovation, and (2) highlighting a specific organization design to manage transparency in a coopetitive project
