Harrah’s Entertainment, the big casino conglomerate, apparently forgot to withhold from about 400 winners (mainly Canadians) at this year’s World Series of Poker®. Harrah’s is now “making up” for this by not allowing these players to play in another poker tournament until they repay Harrah’s. Most likely, the IRS demanded the withholdings that Harrah’s forgot about. For example, a casino must withhold 30% of the winnings of a Canadian (in most cases), though the Canadian can later file a Form 1040-NR to recover some of the withheld tax.
So Harrah’s should have read the rules (but didn’t) or hired a good tax accountant (I happen to know one), and there are a bunch of “lucky” winners out there who Harrah’s would like to collect from.