You'll notice there's no "clans not allowed to apply" list anywhere in these forums. There isn't going to be one either.
My thoughts are this, some clans are more anal about what clans they will and will not play based souly on reputation or hearsay.
Any clan is welcomed to join in on this, the more the merrier. I'd like to see every active clan get involved, but I know that's unrealistic. But I'd rather aim high and fall a little short than aim low and achieve, only to regret not setting my goals higher in the first place. Currently I have 12 vacancies, but that number is irrelevant - could go up if necessary.
Back on topic, due to the flexible "open" format of things in the league as long as at least a few clans signed up will play you your clan is capable of earning points and that, along with fun, is all that really matters.
So if Clan A signs up and you know they don't play your clan for whatever reason, simply play Clan C, D, E, and F. No worries. No big deal.
I hope everyone enjoys themselves with this. The games are set up to be short (10 mins) and there's no waiting for melts obviously so the action should be fairly fast. Looking forward to getting things started.