According to docs, obtained by TMZ, Ronald Sweeney claims Wayne hired him in 2005 to help renegotiate his deal with Cash Money. You'll recall Weezy beefed with Cash Money honcho Birdman over how much Cash Money paid out to Wayne's label, Young Money.

Long story short ... Lil Wayne settled that Cash Money lawsuit in May 2018, but Sweeney now claims he only got a few payments from that settlement ... and they were nowhere near what he says his full cut should be.

Then there's this ... in the suit, filed by attorney Ed McPherson,  Sweeney says back in May 2018, Lil Wayne asked him to fire Cortez Bryant -- Weezy's manager and childhood friend -- over a conflict of interest in a legal dispute involving Drake and Cash Money.

Sweeney says he did so, and took over Bryant's duties and got Wayne to give him a pay bump from 10% to 17% commission. But, Sweeney claims Bryant and Mack Maine then conspired to drive a wedge between Wayne and Sweeney, which allegedly worked. Sweeney says Wayne fired him in September 2018.

Then, this past June, Lil Wayne sold his masters to Universal Music Group for more than $100 million. Sweeney doesn't seem to be asking for any money from that deal ... but brings it up seemingly to point out Wayne has the cash to pay him what he claims he's owed.