Sleek Audio, SunTrust Bank and Lastonia Leviston (Rick Ross's baby mama) are 50 Cent's biggest creditors.

The three entities have teamed up to draw up a payment plan, and have submitted it to bankruptcy court for the judge's approval.

According to documents seen by TMZ, 50 has fired back at the plan, saying it would result in "a near-indefinite period of involuntary indentured servitude" where he has to work solely for the creditors' benefit.

Specifically, he's objecting to it on the grounds of the 13th Amendment -- which bans slavery and other forms of involuntary servitude.

"The plan conditions [50's] access to food and shelter on the whims of the trustee, who answers only to the [creditors]," 50's lawyers argue in newly filed documents.