Participants submitted up to five models for each target. With the exception of T1195-11197, R1138, and R1156, each conformational state was designated as a separate target and for these cases participants were asked to rank the five models according to expected accuracy. The primary CASP metric for protein tertiary structure accuracy is GDT_TS, a multi-superposition measure of backbone similarity between computed and experimental structures (6, 7). The main measure for protein multimeric target accuracy is the interface contact score (ICS), evaluating success in reproducing interface contacts (8). Other metrics are used as appropriate. Several metrics of backbone accuracy were used for RNA structures (9).