As I'm reporting in tomorrow's Daily Variety (and you can read now online), original "Guitar Hero" developer Harmonix has sued the game's current publisher Activision for more than $14.5 million in allegedly unpaid royalties. But between the time I started reporting the story this morning and when I finished up this evening, Viacom (Harmonix's corporate owner) withdrew the suit.

Essentially, the now defunct lawsuit claims that under Harmonix's agreement with RedOctane (the first publisher of "Guitar Hero," which was subsequently bought by Activision), it is owed the higher of two royalty rates if any sequel that it doesn't develop "incorporates, uses, or is derived from Harmonix property." In addition, when that happens, it is also supposed to be paid a royalty on any related revenue from song downloads, in-game advertising, consumer products, etc.

However, if there's a "Guitar Hero" sequel that doesn't use any of Harmonix's work, the suit says, the developer is owed a lower royalty rate, half of the higher, and doesn't get any cut of song downloads and other ancillary products. Harmonix claims that Activision is trying to pay it the lower royalty rate -- which would mean Neversoft essentially built "Guitar Hero III" from scratch -- but it is owed the higher rate. That translates into $14.5 million and counting from "Guitar Hero III," an unknown amount of money from song downloads and other products, and future losses that "will mount at the rate of tens of millions of dollars per year."

Activision isn't admitting that it did anything wrong and in fact its general counsel told me "Activision believes that it has made sufficient payments to Harmonix and the claims otherwise do not have merit." But it was apparently spooked enough that it has agreed to further discuss the issue with Harmonix, which prompted Viacom to withdraw the suit less than two days after filing it.

There are lots more details, but rather than summarize them all, I'll just encourage you to read my story on Variety.com.