The third step in the protocol creates a coverage report that gives the number of times each parameter in OpenFF 1.3.0 is exercised by the molecules in the dataset. Any molecules that could not be parameterized are discarded. All molecule conformers that could successfully be parameterized are exported as SDFs and used for the following geometry optimization. In this step, a total of 60 molecular structures (of which 40 from the proprietary and 20 from the public set) were not successfully parameterized, and were therefore removed from the combined dataset. Our pruned set going into QM minimization contained 19,653 molecules, of which 10,121 were from the public dataset, with unique chemical connectivity.