Feeding 9 billion people by 2050 on one hand, and preserving biodiversity on the other hand, are two shared policy goals at the global level. Yet while these goals are clear, they are to some extent in conflict, because agriculture is a major cause of biodiversity loss, and the path to achieve both of them is at the heart of a public controversy around ‘productive’ land use and biodiversity conservation. Over the years, the scientific, policy, civil society and agri-business communities have been engaged in producing evidence that can support a land sparing policy (separating intensive agricultural production from biodiversity conservation) or a land sharing policy (integrating the two in larger and more extensive landscapes). This paper contributes to this debate by analyzing land sparing and land sharing (LSS) as a socio-technical controversy. Through the analysis of large and small corpora of scientific, corporate social responsibility and sustainability standards documents we explore the ethical underpinnings and social networks that support the opposing sides of this controversy. We explore these linkages in order to explain how the concept of land sparing achieved dominance in the scientific literature and how the concept has been translated into practice. We examine the convergences and divergences in alliances between actors in this controversy in order to map how specific actors have promoted the concept of land sparing as the best way to used land for biodiversity and food production.