[ShabbosGoy]

Is selling Trojans illegal? If so, why are companies like Punkbuster and nProtect allowed to develop anticheat software?

A lot of AC software runs in ring0 and behaves a lot like a Trojan. I remember nProtect specifically injecting DLLs into explorer.exe among other nasty "black hat" techniques.

[sillysaurus3]

It's a difference in kind, not degree. The trojan in this case was meant to harvest banking and Amazon logins.

[ryanlol]

Intent matters.