Supporters of the amendment framed it as the first step in making transparent ownership registries the international norm, with the ultimate aim of ramping up pressure on the US to follow suit.

This is a long way from the end of offshore secrecy, however. Investors who want to keep their identities secret will simply up sticks to another tax haven, says Alex Cobham, chief executive of the Tax Justice Network, a pro-transparency advocacy group.

Secretive US states like Wyoming and Nevada will pick up business, he predicted, perhaps along with UK crown dependencies Jersey and Guernsey, which won’t be hit by the legislation. If businesses are happy to move to avoid transparency, it will be tricky to push the US in line with Europe’s wish for corporate ownership registries to become the global norm, says Maya Forstater, a visiting fellow at the Centre for Global Development: high levels of secrecy will become “a competitive advantage for US jurisdictions.”

Cobham says it’s possible that some of the targeted UK territories could declare independence—though doing so would mean losing one of the most attractive things they offer investors: access to Britain’s trusty judicial system. So, it’s crucial the UK government helps them transition, he says: “To put this through as an imposition without any related plan for significant financial support risks imposing real costs on the poorest people in those territories who are already suffering from the inequalities that come from being a financial secrecy jurisdiction.”

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