So what happens if you are Matthias Mueller, the CEO at Porsche, and a little brown envelope falls through your letter box one day marked; “Reasonably Urgent” – and it has a state of New York post mark in the top right hand corner?

And then you open up the envelope to find a letter inside that reads; “Hello, we are from New York, we are in the banking business. What you did to us in 2008 regarding your company’s bold but ultimately doomed attempt to take over VW has left us so skint, and so angry, we are suing you for one billion dollars. Worst regards, us, from New York.”

How are you supposed to react? Do you pick up the phone, call Wendelin Wiedeking, and ask him nicely if he might fancy picking up the tab? Do you wander around your office for a while before sitting down again in a pool of your own sweat? Or do you merely sit there, wide eyed, wondering if you are hallucinating or not?