[account42]

> If you have a ship that hasn't paid its docking fees, what can you do?

You can sue the owner. If they don't show up that doesn't mean that they automatically win the case - if anything, it's the opposite. If you can't identify the owner you can make the case against John Doe and still have a state appointed defender represent the owner's rights. You can get a court-ordered injunction to detain the ship until the case is resolved.

I don't see why you need to invent a new legal concept here at all - other that it makes things easier for the state to seize things when they don't need to worry about such pesky things as rights.