> With Bitcoin, where all transactions are a matter of public record, I'd hazard that 'should have known' is baked-in. Who should have known what? After receiv

> With Bitcoin, where all transactions are a matter of public record, I'd hazard that 'should have known' is baked-in. Who should have known what? After receiving any bitcoin (can't be before!) everyone is obliged to figure out if the coin came from a ransomware attack? How? And what do they do if some of the coin was so tainted?