The spell thief ap support item isn't procking like it should. I played a game as morgana support (main) and her W pool spell only would be able to proc the item once, unless they stayed in it for more than 3 seconds then it would do another stack. The spell tics damage and procs thuderlords but not the items gold. This is a huge issue for supports like morg and brand who use their spells like this to build up their gold.
They changed the way it works http://imgur.com/LZFE3y1
Not sure if it is a bug or how it is now but I have seen a post earlier about the same thing! Apparently it is only morgana's pool that does not proc the gold you receive from spell thief's more than once. You lay down morgana's pool and it may hit them three times but you only receive gold for the first proc. I don't like it that way either I think you should get gold for each proc of damage but we just need to accept it for now.
procs every 1.5 seconds on persistent effects. it's in the patch notes under spellthief.
It got changed so DoT don't free get yourself gold without working for it .. deal with it.
