Until the Panama Papers, governments had turned a blind eye to their existence and function, taking care not to press the havens to obtain information about the identity of account-holders.

The Panama Papers were exposed by an unprecedented leak from an unknown source to the German newspaper Suddeutsche Zeitung, which went on to share them with the International Consortium of Investigative Journalists. The documents came from the database of the world's fourth biggest offshore law firm, Mossack Fonseca, which acts for 300,000 companies – more than half of which are registered in British tax havens, as well as in the United Kingdom. It is the worldwide revelation of the beneficial owners of those offshore companies – including many wealthy and highly placed people in a number of countries – that has led governments to start working out what actions they can or should take against their citizens and the tax havens they use.

Transfer pricing is a completely different matter. This technique, developed by multinational corporations, has been out in the open for at least the last 25 years, with more and more devastating consequences for governments and their citizens around the world. The multinationals have perfected the practice of selling to their global affiliates at prices that would send the affiliates bankrupt if they were left on their own, trying to recover their inflated import costs in the marketplace.

The affiliates survive only because the banks of the world lend them money based on surety letters from their parent companies or regional head offices. This process has allowed multinational firms to dominate the markets for goods and services in around 180 countries, or to operate without permanent establishments and to have no tax obligations anywhere. This trick relates principally to internet operators such as Google, Amazon and Apple and to "sharing economy" companies such as Uber and Airbnb.

There are approximately 500 multinational companies in existence, who control about 60 per cent of world trade, and whose brand names are familiar to the media and the population. Most of the world's major economies are members of the Organisation for Economic Cooperation and Development, and have participated in its major meetings in Paris over the last two years, where the core problems caused by transfer pricing have been clearly expressed and discussed. As a result, the governments of many major economies have recently subscribed to a level of mutual tax co-operation that has never been previously known.