Sometime around August 2000, a letter arrived on the desk of Osamu Nagayama, president of Chugai Pharmaceutical, the contents of which were heresy to the conservative Japanese drugs industry, and “almost taboo” across corporate Japan.

What was most surprising about the concise, two-page memo was not its unconventional plan – in which a large, non-failing Japanese company voluntarily submitted itself to takeover – but, says Mr Nagayama, “that almost nothing in the letter needed changing”.