There is a building in Wilmington, Delaware.
It is not large. It is not remarkable. If you drove past it you would assume it held a law office and a dentist.
Hundreds of thousands of companies list it as their legal address.
Not a few hundred. Hundreds of thousands. Major corporations you buy from every week. Banks. Airlines. Retailers. Technology companies.
When people first hear this, they assume something shady is going on. A loophole. A scheme. Somebody getting away with something.
The truth is stranger and much more boring, which is exactly why it works.
Let me explain what is actually happening in that building.