So Harmonix, did Neversoft/Activision ever request compatibility?

[Xzyliac]

no, it is not

Yes it is. RedOctane publishes GH Activision just owns the name. EA has involvement in the development in the same way RedOctane does.

Neversoft/Harmonix develop software (although Harmonix has input). MTV provides artistic benefits and own Harmonix as a network.

Long story short EA and RedOctand decide if one supports the other.

[Magnet]

Yes it is. RedOctane publishes GH Activision just owns the name. EA has involvement in the development in the same way RedOctane does.

Neversoft/Harmonix develop software (although Harmonix has input). MTV provides artistic benefits and own Harmonix as a network.

Long story short EA and RedOctand decide if one supports the other.

Here's a small bit from Wikipedia (I remember this statement from a long while ago even though it's strangely difficult to find on the internet now):

Harmonix has confirmed Guitar Hero guitar controllers will be compatible with the game, as well as other third-party guitar controllers.[11][7] The company has also said that Rock Band will also support the use of additional third-party controllers, and, should Activision (the current publishers of Guitar Hero) request it, they can make the Rock Band guitar controller work with Guitar Hero III: Legends of Rock.

It certainly sounds like it's between Harmonix and Activision, which makes the most sense. Harmonix may not be the one who can make the RB controller work with GH3 (unless they're working with creating the hardware as well as the software?), but I think they have a vested interest in the matter since they were formerly partnered with RedOctane. Maybe EA doesn't care less about the issue, but HMX might like to see their former franchise play with their new guitar.

And I don't know what you mean by Activision just owning "the name." What name? Activision owns the company of RedOctane completely now. Activision is publishing GH3.

[Phrank-E]

Actually I think it is between RedOctane and Harmonix.

RO are the ones that make the peripherals for GH, as HMX made RB peripherals.

I believe it would be up to them. But if that were true, I think RO would allow it. It's Activision who are the a-holes.

RO was built upon making DDR pads for the Konami games.. Now, Knowing this, I found it repulsive that when the TAC Fling V guitar controller came out that RO changes the code around on GH2 to disallow the TACs use. Hypocrisy.

This was long before Activision bought them out. So I would say NO! RO would not allow it. Activision or no Activision.