This actually seems to be an edge case that falls through the rules as written. You can't know that you're peddling counterfeit goods without violating the law, but you can negligently "whoops-didn't-mean-to" sell counterfeit goods. And as soon as you officially know, you put a hard halt to things there. So the manufacturer has to play whack-a-mole with the counterfeit suppliers to various points in the supply chain.