The developer of PuzzLoop has threatened to sue PopCap Games, the developers of Zuma, but has so far declined to persue any such action. Unless they do sue PopCap Games and a court rules in their favor there is no reason for the game to be pulled, unless PopCap Games decides to voluntarilly concede Mitchell Corporation's right to the design.
Also, it's important to note that the claim is concerning the design, not the code itself. As far as I know, PopCap developers coded the game from scratch, but used the same general design. Thus, they did do all of the work aside from creating an entirely new look.
John
I was not sure where to post this, but Zuma should not be available for download here. Zuma is an illegal copyright violation of an arcade game from 1998 called PuzzLoop. Really, the fact that it exists is bad enough, but to tell people "you have to give us $20.00 for a game in which they only work we did on it was to turn the launcher into a frog". They didn't earn that money, so at no point should they be allowed to make any off of it.

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