Comparing the three prioritization approaches across the substrates in Figure , we found that the Ring Breaker model consistently predicted the first applicable ring formation with a lower rank than both the standard and filtered models across the Reaxys and USPTO datasets (Figure and Figure ). Notably, there appears to be missing values for the filtered model on the Reaxys dataset (Figure ), this is because the values lie off the range covered by the axis. The lowest ranked prediction for the filtered model on the Reaxys dataset was 133, and the median prediction rank was 736. This highlights an interesting discrepancy between the standard and filtered models trained on the Reaxys dataset. The difference can be explained by considering that the standard model was trained on all templates, and the filtered model is obtained by applying a filter to the standard model, to leave only templates which in the reaction dataset had been recorded as contributing to a ring formation. In the case of the standard model, the templates that correspond to ring forming reactions in the reaction dataset cannot be prioritized by the model. Therefore, once the predictions from the standard model are filtered, none of the remaining templates that correspond to ring formations in the underlying reaction dataset are applicable within the top 50 predictions (Figure ). The standard model is therefore prioritizing and applying templates that can be used in the context of ring formations in silico but have never been recorded as a contributing to a ring formation in the underlying reaction dataset. Thus, this explains why the standard model can predict ring forming reactions in the top 50 whereas the filtered model cannot (Figure ). Comparatively, the Ring Breaker model is able to prioritize and apply more templates in the top 50 predictions, than either the standard or filtered models as applied to the substrates in Figure (Figure and Figure ). ). The standard model is not able to prioritize templates that have been used in ring forming reactions as effectively as 'Ring Breaker', as demonstrated by filtering the standard model. Thus, for the Reaxys dataset, the first applicable template for the filtering approach is ranked as 133, and the median rank 736, even after filtering all templates that have not been recorded as forming a ring in the reaction dataset.