The US IRS is yet to issue guidelines on whether prediction market gains should be taxed as derivatives, gambling winnings, or income, worrying accountants (Kate Knibbs/Wired)
https://www.wired.com/story/nobody-knows-how-to-file-taxes-on-prediction-market-wins-and-losses/
http://www.techmeme.com/260407/p18#a260407p18
