The recently purchased section among the champs is a complete mess
So yeah when you look at the champs in your profile you can choose to let the client only show you certain champs based on a category,like only those you own or the ones you don't own.
Among these options is the "recently purchased"-category and it seems to be completely broken.
I mean seriously my latest champion purchases were

&
but when I choose the "latest-purchased category" it tells me that my latest purchases are
&
despite the fact that I bought them in 2012 and 2013(except for azir for obvious reasons).
Karma,Hecarim and teemo wouldn't even be in the top 10 of my recently bought champs.