The perm functions but the CP doesn’t – only the perm can accurately calculate the prize by pinning it to patent profit

In comparison, a prize system that allows the patentee to claim an amount equal to its own profit (or, say, half of its profit) would be much simpler to administer. The patentee would have every incentive to collect information on the total profits from his own patents, and to submit such an estimate to the government every year to gain a prize. The government would not have to expend resources on aiding or organizing patentees to seek prizes. The government would have to check that firms are submitting accurate information on profits from patents, and presumably would conduct occasional audits. But these administrative expenditures would not be different from what the government already spends in collecting and reviewing tax submissions by corporations and individuals.