The global extent of biodiversity offset implementation under no net loss policies

'No net loss' (NNL) biodiversity policies, which seek to neutralize ongoing biodiversity losses caused by economic development activities, are applicable worldwide. Yet, there has been no global assessment concerning practical measures actually implemented under NNL policies. Here, we systematically map the global implementation of biodiversity offsets ('offsets')-a crucial yet controversial NNL practice. We find, first, that offsets occupy an area up to two orders of magnitude larger than previously suggested: 12,983 offset projects extending over 153, 679(-64,223)(+25,013) km(2) across 37 countries. Second, offsets are far from homogeneous in implementation, and emerging economies (particularly in South America) are more dominant in terms of global offsetting area than expected. Third, most offset projects are very small, and the overwhelming majority (99.7%) arise through regulatory requirements rather than prominent project finance safeguards. Our database provides a sampling frame via which future studies could evaluate the efficacy of NNL policies.