don. His net worth is probably between f80m and f100m. This pushed him up to about 80th on the rich list.
Mark Thatcher left Britain in 1994 after revelations that he had won a commission in a £300m contract with Oman during his mother's visit there three years previously.
Regular job
He took up a job as American agent for Lotus Cars, a company owned by an old Thatcher family friend, Alan Curtis, on a comparatively modest salary of £45,000 a year until 1986. It is the only regular employment he is ever known to have had.
Basing himself in Dallas, he established a personal and business relationship with Ross Perot, the right-wing populist presidential contender in the 1992 elections and a key player in the Irangate scandal.
In 1991 Mark Thatcher took out Swiss resident status on the grounds he was consultant to the Lausanne branch of a Portuguese banking and investment company, Espirito Santo. He thus enjoyed an income tax rate of only 12 per cent.
Throughout his nine years in exile, Mark Thatcher made most of his real money from introducing private arms and munitions manufacturers to key contracts in various governments.
There is nothing to say he ever acted illegally. Merely furnishing introductions where no specific deal can be shown to have occurred as a direct result, and receiving money for the introduction rather than the sale, is legitimate business practice.
As Gerald James, the former chairman of the defunct munitions manufacturer Astra Holdings commented: "No one is ever going to find a piece of paper with Mark Thatcher's name on it".
In 1992 James gave evidence to the House of Commons Select Committee on the Iraqi supergun affair, claiming that Mark Thatcher was among the British nationals who received commission from Britain's f20 billion Al Yamanah II (AY2) weapons contract with Saudi Arabia in 1985, the biggest arms deal in history. The deal took place only after the personal intervention of Margaret Thatcher.
£1m house British Aerospace was a prime beneficiary of AY2. The tillery to Jordan, again in 1983, as part of a deal in which Thatcher junior netted £1 million; and helicopters to Saudi Arabia in 1985 in a package worth £1.5 billion.
Malaysia
In 1987 he was involved in a £2 billion contract with Malaysia, taking a share of the £65 million fees with other British business people.
The most explicit allegations about Mark Thatcher's career are contained in the book The Profits of War, written by Ari Ben-Menashe, who formerly worked in the Israeli prime minister's office.
Ben-Menashe points out that the Israeli secret service, Mossad, often "takes out" people involved in the supply of arms to "Little Major will be quite unable to hold the party together -of that we can be sure. My guess is they will ditch him before the next general election, Conservatives will give us the delightful choice of Mr Kenneth Clarke or Mr Michael Portillo as our next Prime Minister... "The 'soul of the party' will be fought over by the yobs, represented by the neo-Fascist Portillo, and the slobs represented by the smug Hush Puppy Chancellor. "True Tories...must vote Labour and do so/enthusiastically." AN. Wilson. Evening Standard, October 14.