Mariner's Vengeance Working On Shaco's Clone

Hey there, I've just recently finished an ARAM game of Shaco, where I discovered a bug involving his clone and Mariner's Vengeance. In particular, Mariner's Vengeance appears to be an active effect on his clone once purchased, in that the clone will undergo the effect each time before it dies. This seemed to happen regardless of whether the item itself was actually on cooldown.