The GBT-Big was identical to GBT-Small, except it included 10 additional mates, 5 trained using counted FCFP6 fingerprints (rather than binary used to train small) and 5 built using AtomPair fingerprints. Each of these sets of 5 mates were trained the same way as the GBT-Small model. The addition of the counted FCFP6 and AtomPair were chose because they are easy to calculate and covers both circular and non-circular fingerprints.