This paper investigates the effects of accounting and management control devices in mediating hybrid relations in complex organizations. We focus on organizational complexity and institutional hybridity in pharmaceutical and biotech R&D, a site where macro concerns for the productivity of drug discovery and development pipelines are often riddled with tensions between commercial, corporate, and science logics. We propose a theoretical approach based on socio-materiality studies, the science and technology studies literature and concepts of technological mediation. Within this approach, human actions and choices are mediated by technologies and material calculations. We look at the accounting mediation of institutional logics as instantiated in budgetary and performance measurement technologies. Whereas past literature has focused on the work of segmenting and combining logics as performed by human actors, we find that hybridity can be a property of relations between institutional logics where material accounting devices provide the calculative conditions for mediating such logics. We, thus, contribute to the literature on institutional logics by identifying and characterizing the key logics of practice at play within complex sites. We also contribute to the literature on hybridity by spelling out the mechanisms of mediation between commercial and science logics: balancing, prioritising, legitimating, regulating and blending. By doing so we show how the management of hybrid relations in scientific discovery in pharma commonly rests upon material calculative devices that can span multiple logics.