Rule 5 does a final check for enantiomorphic ligands. Note that implementation of Rule 5 is not just a check of the lists generated using the procedure of Rule 4b, as priorities may have changed after application of Rule 4c. Consider the digraph in Figure , which shows the digraph of Figure , ranked by R-and S-reference for both Rule 4b and Rule 5. Here we see that after application of Rule 4c, the sorting is changed, and Ligand A has preference over Ligand B by Rule 5.