The Scottish Premiership club changed their kit manufacturer from Hummel to Castore in 2020.
Rangers announced ahead of the 2020-21 campaign they were switching to a new kit and retail operations partner following the conclusion of all existing contracts.
However, Elite – the exclusive brand partner of Hummel – lodged court papers to challenge the decision last year.
They went into administration shortly after but have decided to pursue the case.
Elite’s legal team insist Rangers breached a contract which allowed them to provide kits after signing with Castore.
The Ibrox club revealed in their recent accounts that they had not set money aside for the court case.
Rangers believe the claim was not likely to succeed, and it will be interesting to see how things go.
The five-year kit deal with Castore was worth £4m per season.
Shortly before going into administration last year, Elite won a bid to discover how many kits Rangers have sold since switching to Castore.
While they have always wanted £9.5m as compensation, Elite requested more information concerning the sales data.
It would help their legal team prepare their case and see how much they should claim in compensation.
A series of hearings at the Court of Session in Edinburgh is expected in the coming weeks and months.
Rangers will fancy their chances of winning the case, but Elite will be ready to keep fighting.
The Gers have struggled to keep pace with Celtic this season and will hope to beat their local rivals in the Scottish Cup semi-final next Sunday.
They lost the final of the Scottish League Cup to the Hoops and are 12 points behind them in the league with six games left.
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