Note that while CLEG notation is always read from the left to the right., ">>" does not specifically indicate going from a supergroup to a subgroup. Rather, it simply denotes a change in basis and probably in symmetry as well. Symmetry may have been lost or gained, or left unchanged. This particular case, the basis for space group 10 is being transformed into the basis for space group 13, and the operations are now those of space group 13 in its reference setting.