Given the diverse, spontaneous inputs from the initial round of the open competition, and the high quality of the associated dialogue that had taken place on the relevant project website, GitHub, it was decided that a second round would be run in 2019 since "expensive failure analogs" were still arising in the experimental programme. The aim for this round was not only to allow for the entrants from Round 1 to improve upon the original models, but for new participants to get involved with inputs from larger companies that specialised in artificial intelligence and machine learning (AI/ML) approaches. Since the series had moved on in the interim (with further compounds being evaluated), the community had access to an expanded dataset, including all the data used as the test set for the previous round .