For reaction completion, all incomplete reactions in USPTO dataset from the ChemBalancer subunit were passed to ChemMLM for missing molecule prediction, whilst only 1% from Reaxys ® was randomly sampled and fed in ChemMLM. This is because the missing molecule prediction by ChemMLM was computationally expensive, which makes it harder to process the larger scale Reaxys ® reactions data. Statistics for the reaction completion results are shown in Table , and this was concluded from all USPTO reactions and sampled Reaxys ® reactions.