One idea may go across several people's head. There could be a confusion then as what is copied and what is not. It doesn't happen in blind contests, though posts may be similar but idea can't possibly be copied. So if an idea comes to a designer's mind after reading the brief, he should go through all the other posts and see if somebody else had it before.
Edited by 3187mohit, 17 March 2013 - 04:57 AM.