U-God has contributed to 170 Wu-Tang tracks since the group's inception in 1993.
In a new lawsuit he says he hasn't been paid royalties on any of them in six years.
He also alleges he hasn't been getting any of the biannual checks for Wu merchandising that he was supposed to receive.
On top of that, he's seen no money from the secret Wu-Tang album Once Upon a Time in Shaolin, which Martin Shkreli bought last year for $2 million.
All in all, U-God is asking for $2.5 million from Wu-Tang.
In U-God's filings, he makes it clear that RZA and his brother Mitchell Diggs are the ones who are denying him his money.
U-God isn't the first Wu-Tang member to question RZA's recent leadership. But he is the first to put a lawsuit behind it.