The Migos rapper is the middle of a bitter legal war with Quality Control Music, and according to new legal docs, obtained by TMZ Hip Hop, the saga began in 2013 when Offset agreed to produce solo records for the label.

Things were well and good until 2015 when Offset claims Quality Control entered into a separate deal with Capitol Records -- the result of which was QC ended up owning 100% of any future Offset solo records created between 2018 and 2023. We'll come back to that.

In a response, filed by his attorney Bryan Freedman, Offset claims everything changed in 2021, when he and QC broke up and hammered out a new deal where he regained control of his solo work for everything he produced from January 2021 forward.

However, Quality Control says not so fast ... the label claims it still holds the rights to Offset's solo music based on the prior deal with Capitol Records, an argument Offset now insists is ridiculous.

The way Offset sees it ... QC walked away from the rights to his music when it cut the new deal with him in 2021, and he alone controls his solo masters from that point on.

Obviously, there's a ton of money at stake in this dispute, which is working its way through the courts ... and it's hard not to compare the situation to what we've seen in the past with Taylor fighting her old record label.