It is very unlikely to occur, but never say never when large sums of money are involved. If someone came up with enough money, Hasbro would sell WotC in a heartbeat. However, I can't imagine anyone feeling that right now it's worth it. This kind of sale only works if the IP is in a state of flux, where the host company doesn't want the risk anymore and the purchaser is willing to take on the risk, but WotC is anything but in a state of flux. Theoretically if Hasbro was suffering from severe cash-flow issues (unlikely) they might sell off some companies, but they're much more likely to sell ones that aren't doing well, rather than ones that are almost certainly cash cows.