When shareholders react savagely to CEOs selling shares, the usual thing to do is assure them that one is mostly just paying tax, a mortgage or funding some other boring but unavoidable outlay. But that isn’t David Dickers’ style.

His listed computer parts business Dicker Data crashed 21.4 per cent in the three trading days after the executive chairman cashed out $42.2 million worth of shares via a Barrenjoey-administered block trade. Conducted, incidentally, on the very day the stock hit a record high.