Dataset of the 49 experimental binding affinities used in this work, adapted from Refs. [7,32]. Energies are expressed in units of kcal/mol. The prefix H- or L- indicates whether the mutation was made to the heavy or the light chain, respectively; letter pairs at the end of some of the mutants correspond to the residue insertion code relative to the germline sequence, followed by the 1-letter code of the residue after mutation. The reversion mutant definitions are taken from Table S10a in Ref. [32]. They are: H-4rev—A56G, V57T, P62K, V73T (heavy chain); H-7rev—T33Y, G55S, A56G, V57T, P62K, V73T, Y74S (heavy chain); HL-11rev chain: I30T, K52N, R53N, G54S, A56G, V57T, R61Q, P62K, V73T, Y74S (heavy chain), Y28S (light chain).