[GAMEPLAY] Aatrox passive cooldown not working properly when out of combat

Aatrox passive tooltip says this about its cooldown, "225 second Cooldown and decays by 2% while out of combat." This out of combat portion never gets activated so either the tooltip is wrong or it is not working properly. On the wikia, it says that the passive cooldown is 225 seconds and it doesn't even mention the 2% decay. I looked at patch history for Aatrox and it was never changed to remove the 2% decay so I'm not really sure which one is correct. Either way, every time I've tested this, my passive is down for the full duration of 225 seconds even if I stand on fountain for a while.