A rep for Wayne tells TMZ ... Lil Wayne was a Cash Money artist and it was their responsibility to pay David Banner, not Wayne.If Lil Wayne doesn't know what the word "ironic" means, he does now ... he's being sued by a rapper for not forking over royalties ... which is exactly his gripe with Birdman.
Rapper David Banner claims he signed a contract in 2008 with Wayne's Young Money Records to produce two songs for Wayne -- "La La" and "Pussy Monster" -- featured on "Tha Carter III."
Banner claims Young Money told him in 2012 he was owed $138,787.19 in royalties ... but he never saw a cent. Banner also claims Young Money has gone radio silent, so he has no idea how much more he's owed.
Banner also says the same thing happened in 2009 with "Streets Is Watchin." He claims he was told he's owed more than $15,392.57.
As TMZ first reported, Wayne is locked in a lawsuit against Birdman and Cash Money Records for $51 million ... claiming he's owed money for his never-released album, "Tha Carter V."