A EXPERIMENT PROTOCOLS Pre-trained Models. We apply ChemSpacE, as well as baselines, on two state-of-the-art molecule generative models with publicly available pre-trained models. HierVAE and protein binding affinity, synthesis accessibility oracles in TDC . In total, we analyze 212 molecular properties from multiple dimensions, including distributions, intercorrelations, etc. Details can be found in Appendix G. Due to the page limit, we mainly report results for 7 molecular properties, including 4 very common yet important ones, drug-likeness (QED), molecular weight (MolWt), partition coefficient (LogP), synthesis accessibility (SA), and 3 binding affinity scores. For continuous molecular properties, we take the molecules with largest and smallest properties for training the linear models.