Bounty gold bug or?

I was wondering if there is a bug with bounty gold? I killed lee sin (who was 13/0/4), and the bounty was 350g, no 500g the max? How come? Or is it just a typing error? http://imgur.com/O1IssoN,3lnhnJ7#0 http://i.imgur.com/3lnhnJ7.jpg

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