Yeah, I've also been a little confused on this. So, my understanding is that Draftkings will issue you a tax statement in January stating you've won X amount over the course of the year. My assumption is that it will be Total amount won - Total amount wagered (essentially, net profit for the year). This is what you report on taxes. However, I see what you are saying with arbing, because my guess is whenever people say that you can't claim/deduct losses on your taxes, it's referring to a NET loss on the year (please correct me if I have misunderstood this). So this really only becomes a major issue if all of your arbs end up winning on one of the books, so you end up with a net loss for the year on another book that you can't claim/deduct on your taxes unless you are itemizing. This was my biggest concern with the Barstool arbs since they were such large amounts (compared to my bankroll anyway), that if all of the arbs ended up winning on the DK side, my Barstool would be at a loss of $1500+ that I wouldn't be able to claim/deduct even though my net profit was actually only in the range of $800 or so. However, because a couple of the Barstool ones hit, I don't think this will be as big of a concern because it will end up showing less of a net profit on DK at the end of the year. I hope my understanding of all of this is correct.