Let's take for example Farmville social game. Many clones have appeared and they have very similar concept, most of them have in the same way Neighbor, tools, etc. So legally, where is the edge of how much concept can be copied. Or is just like that the concept can not be legally protected but only a design?
It would be logically that this could be protected. But how, what can be protected here? Also in web portal you could say that others are not allowed to copy the same registration process for example, but every x portal has it the same.
So legally, how much concept can be copied?