They are suggesting that the treaty has a loophole that companies can make shell companies to outsource profit to non-signatory tax havens. Of course, that is

They are suggesting that the treaty has a loophole that companies can make shell companies to outsource profit to non-signatory tax havens. Of course, that is stupid. That loophole is what happens now, and the point of such a treaty would be tariffs or sanctions against non signatories.