Viacom wants a refund on Rock Band

Viacom agreed to pay Harmonix earn-outs if Rock Band exceeded certain financial targets. Viacom paid the earn-outs, but now wants a significant refund, based on lower earnings and an "adjustment clause" which would allow Viacom to correct any overpayments. However, given that Viacom owns Harmonix it's unlikely we'll see this case in court anytime soon.

Coverage here (Gamasutra).