retroactively applying a law is not very conducive to making predictions about legal matters, and therefore, it's very rarely done (if at all?).
Plus, even if blackbird has to pay back their collected fees, they can "just" bankrupt - after all, the money is gone (unless you are implying that any dividends/payment to employees etc, are clawed back...)
> Plus, even if blackbird has to pay back their collected fees, they can "just" bankrupt - after all, the money is gone (unless you are implying that any dividends/payment to employees etc, are clawed back...)
Money that was already paid is gone, but if you had some settlement where you pay some amount per device, you could stop paying them going forward.
It would also be effective against the use of invalid patents by large companies that wouldn't be bankrupted, which would reduce their incentive to lobby for their continued granting.
