Harmonix founders Alex Rigopulos and Eran Egozny are leading a lawsuit from a number of the developer's former shareholders against current owners Viacom.
It is alleged the MTV-owning company, which put Harmonix up for sale last month, is "manipulating costs" in an attempt to try and avoid bonus payments.
Gamasutra reports that the dispute concerns the initial deal penned between the pair when Harmonix was initially acquired in 2006. The studio believes bonuses of 3.5 times any gross profit made beyond $32m throughout 2007.
The full story can be found over at MCV.