• JPO: a set of 450 chemical structure images from the Japanese Patent Office • CLEF: a set of 992 chemical structure images from the Conference and Labs of the Evaluation Forum test set • USPTO: a set of 5,719 chemical structure depictions from the US Patent Office • UOB: the dataset of 5,740 chemical structure depictions compiled by the University of Birmingham The models were primarily evaluated for their ability to recognise chemical structure depictions accurately. This evaluation was based on two key metrics. First, we conducted a one-to-one string comparison using Canonical SMILES for both the original and predicted SMILES representations. This analysis provided insight into how effectively each model predicts chemical structures from input images of chemical structure depictions, with even a single character mismatch in the predicted SMILES string considered as an incorrect prediction.