Blizzard has not made any mention of banning based on a specific program in a long, long time. People who claim to have been banned for the use of a program are often more likely banned for using said program to violate the rules of the game. In other words, it's not the program, it's the way people use it. AHK just happens to be a program people like to use to do such things.

Like - using the mouse to autocast X every Y seconds as long as the key is held as mentioned in this thread already. That is automation - there is nothing at all wrong with the mouse, but using it to automate gameplay IS a bannable offense. Thread locked.

http://us.battle.net/d3/en/forum/topic/5795159954#11

Omrakos
Support Forum Agent
Posts: 35,118
It does't matter what device or program is used. If it performs a task that automates portions of the game, it could be in violation of the Terms of Use/End User License Agreement and result in an account closure, if detected. I can not give you permission to use any such device or application. If you choose to use it, you do it at your own risk.
http://us.battle.net/d3/en/blog/10319928

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