When the game launched, the weekly cap of exp a clan could receive from its members was 100,000. Recently, in-game, on the Destiny app, and bungie.net lists the cap as 266,667. This seems to be pretty clearly a bug, as the number isn't an increment of 250 (nor is it an even number). While I have no means to realistically test this, as most of my clan is inactive these days, I don't know if this is merely a display error, or if the EXP cap was raised in relation to the changes EXP has received over the recent months.