There's an old argument that I'm not sure has ever been resolved. Fleet Action lists SEVEN clan leaders: Ragitagha, Ki'ra, Sihkag, Sutaghi, Qarg, Kurutak and Caxki. People generally assume that Kiranka, the Emperor's clan, is the eighth... and while it's possible that it's treated as such later, I don't think it explicitly is. There are at least two lines in Fleet Action where it's clear that these meetings have the Emperor, Thrakhath and the heads of EIGHT clans. So that suggests that either the ruling clan is counted separately or that there's an eighth baron at the war council who formally represents the Kiranka clan.