HMRC has quietly sent hundreds of letters to wealthy people asking them to reveal what they own. Not what they earn or what tax they've paid, but what they own. Here's what's going on. A unit called the Wealthy Team covers anyone with "incomes of £200,000 or more, or assets equal to or above £2m in any of the last three years". That's about 850,000 people. The letters ask for a meeting to discuss "sources of wealth", "future intentions", trusts, companies, family arrangements and even "significant life events" you expect in the coming years. It is presented as voluntary, but there's a nudge: "We may still need to carry out compliance checks on your tax returns. However, speaking with you first may help avoid this." Until now, inspectors have usually only asked about income and earnings. Experts call this a "sea change". One lawyer asked the obvious question: "does HMRC have a right to know what someone owns and not simply that they have paid the right amount of tax?" A tax adviser said: "No other G20 country asks for this level of detail from its taxpayers about what they own." So what is it for? Advisers suspect it is groundwork for an exit tax, a charge on your wealth for leaving the country. As one put it: "Building that knowledge could indeed be part of moving towards an exit tax." You don't have to be a billionaire to see the problem.