It is my understanding that quarterly reporting obligations apply to the Mining, energy and exploration lists (ie: those companies primarily in the NL, or former NL sector).
Monthly reporting obligations apply to those companies experiencing cashflow, or financial sustainability issues (ie: many of your smallcaps).
The remainder are on 6-monthly reporting cycles. If, however, they do report quarterly, then I understand that this would be occurring on a voluntary disclosure basis, or due to a dual listing obligation (ie: on the LSX, Nasdaq, or NYSE).
