Of the datasets used, only the United States Patent Office extracts (USPTO) ranging from the years 1976 to 2016 is publicly available. This is split into granted and applied patents and is openly available for use by the community. A subset of the AstraZeneca Electronic Notebooks (ELN) were mined (May 2019) to yield the internal proprietary dataset, considering only positive reactions, classified as those with a yield greater than 1 % and having a conclusion statement. The Pistachio (2017-11-17) and Reaxys datasets are commercially available, provided by NextMove software and Elsevier respectively under licensing agreements. The Reaxys dataset was filtered for multi-step reactions to yield only the intermediate single step records for which templates were extracted. Full details of the number of reactions and unique extracted templates can be found in Table .