I'm exactly two counties away from being able to declare myself Emperor of Britannia. I have a stack of courtiers and other nobles with claims on various bits of English real estate, including several claims on duchies, which I've verified through looking at the claimants for titles.
Unfortunately, I can't go to war against the King of Scotland for any duchies that he has; instead, I have a pile of excuses to go to war over various single counties. I've snipped off duchies before, and I distinctly remember having my choice of duchies to fight over the last time I went to war, but suddenly I'm no longer able to. What changed?
(Note: I have 46 Casus Belli against Scotland. About six of them are about a duchy with a single county in it. Have I run out of Casus Belli?)
Best Answer
I. Weak claimants can only press their claim under specific circumstances
II. Females cannot press claims against titles with agnatic succession laws.
So, when you see a claim that is not available as a CB