When MTV Games bought Harmonix way back in 2006, few people paid attention to a clause which awarded significant bonuses to developers based on sales of the Rock Band series. It appears that even Viacom did not believe it had to set aside money to pay those bonuses, as it only gathered some 208 million dollars this March for such payments. Now the performance of Harmonix means that more than 300 million dollars will go to the company as a reward to the success of their music simulator.

A Viacom financial statement detailed the clause as providing that “to the extent financial results exceed specific contractual targets against a defined gross profit metric through 2008 former Harmonix shareholders will be eligible for incremental earn-out payments with respect to the years ended December 31, 2007 and December 31, 2008”. In other words, if Harmonix's games do better than expected, a significant bonus will be paid to the company.

It seems that the Rock Band series has sold more than 7 million copies worldwide and more than 26 million downloadable tracks have been bought by game players. Kelly McAndrew, a spokesperson for Viacom, has been quoted by Bloomberg as saying that “We may not have anticipated the payment would be that high, but it's based on what they have achieved. If they are making more money for us and we have to give a little back, that's OK”.

Rock Band has emerged as the only real competitor to the Guitar Hero series from Activision and Neversoft. Both franchises have recently released new installments, Rock Band 2 and Guitar Hero World Tour. The former is a success primarily in the United States and has seen some issues related to a promised free DLC pack, while the latter has encountered instrument problems, which prompted Activision to release a drum tune up kit.