Inspired by this Money Stuff column: One sentence of the 940-page [‘One Big Beautiful Bill Act’ passed last week] says gamblers can deduct only 90 percent of their annual losses, instead of 100 percent, which has been the norm.

This has created a funny situation where sports predicting on markets like Kalshi is taxed as capital gains but sports betting on a traditional book like draftkings gets unfavorable treatment around deducting losses.

All questions resolve on tax day 2027 unless otherwise stated. I'm open to moving the resolution date if something legal development is likely to get decided soon after. I'm interested in the short term impacts not the long term, so anything pending would have to apply to the 2026 tax year. If legal action takes place before resolution, I'll leave these open for some time to account for appeals.

Most of these questions are goin to be judgement calls, so I won't predict. I'm not a lawyer or a tax professional. Feel free to add more options and I'll try to adhere to the authors criteria. I'll probably N/A liberally if I can't figure out how to resolve.

Question specific clarification:

Mainstream pro gamblers move primarily to prediction markets for tax treatment

I'll resolve based on media consensus using quantitative methods. Something like survey or industry report. Not "I talked to one sports gambler who moved to polymarket" story.

Administrative Action: I'll resolve based on an act by the federal executive branch even if it's later overruled by legislation or courts. The act just has to go into effect.

Legislative Action: I'll resolve based on an act by the federal legislative branch even if it's later overruled by administrative action or courts. The act just has to go into effect.

Legal Action: If a legal ruling is directly overturned on appeal by a higher court, it won't count. If a separate case changes the outcome it will. As with above, it has to go into effect. Pending appeals will not change the resolution date unless action is imminent.

"Major sports book" questions: for a sports book to count, it has to be already operating above board in the US as of 2025-01-01 and regulated as gambling.