Shell companies — corporate entities whose beneficial owners are unknown — let the worst people in the world launder their fortunes. They have names like “ABC Ltd” or “XYX Inc”. They are incorporated by clever lawyers in lax, privacy-friendly jurisdictions: offshore, onshore in webs that span both. The risk of exposure is tiny. The advantages are huge. The effects are pernicious.

Some countries already place restrictions on shell companies. In the United States, for example, they cannot buy prime real estate in some areas. But global outrage over Russia’s attack on Ukraine gives us a great chance to go far further.

The principle is simple. If these corporate entities want the rights that real people have, such as signing contracts and using the legal system to enforce or defend their claims, they should identify their real owners.

Here’s my plan: anonymous entities should have no recourse to law. Any company (or trust or partnership) that wants to go to court must identify its real owners. That may be one person or several (or many, for bigger, publicly traded companies). But without that information, it cannot sue or be sued.

This simple provision would turn shell companies into outlaws. Few customers and suppliers would want to do business with them, because the necessary contracts could not be enforced. And it is hard to rely on trust alone when you do not know who you are dealing with. Shell companies would of course be free to do business with each other. If they wanted to go respectable, they would just explain who really owns them. It would not be enough to say that the company is owned by another company, or some other form of legal jiggery-pokery. The rule is simple: without living, breathing, credible owners you can have no legal representation and no access to the judicial system.

This would be an immediate and devastating blow to the plutocrats and kleptocrats who hide their identity behind the shield of corporate secrecy. These people—who include Azeris, Uzbeks, Kazakhs, and Ukrainians as well as Kremlin cronies—fear the limelight. Explaining who they really are would open them to embarrassing lines of questioning such as “how can you afford this asset on your official salary?”

I would go further. The next stage would be to say that all shell companies that own real estate must provide a beneficial owner the next time they file their property taxes. If they fail to do that within a year, the property is forfeit: in effect, it belongs to the state.

A law-abiding, respectable owner will have no difficulty in meeting this rule. But the kleptocrats will find it very difficult. They could try nominating a lawyer or some other crony — but then the question will immediately arise of how this person managed to afford the property. In Britain, it could lead to the issuance of an “Unexplained Wealth Order” — a powerful but rarely used weapon in our anti-corruption armory.

This approach will have two laudable results: a flood of new information about who owns what, and a large lump of useful money flowing from those unable to identify themselves. In theory, those affected might bring a human-rights challenge citing confiscation of property. But to bring such a case, the litigants would have to identify themselves — thus solving the problem.

The same principle could be applied to other trophy assets such as yachts and private jets. But real estate is the easiest target because it is immovable.

The funds raised could go into general public spending. But I would prefer a different purpose: to endow a fund for the reconstruction of Ukraine.