An anti-Adani protester (Image: AAP/James Ross)

Overnight the world’s biggest investment fund, BlackRock, said it would dump more than half a billion dollars worth of thermal coal shares.

The announcement was part of an extraordinary letter urging company boards to step up their efforts to tackle climate change -- from none other than the world’s biggest fossil fuel investor. 

BlackRock has long faced the wrath of environmental groups and shareholders alike for propping up some of the world’s biggest polluters. The group manages upwards of US$7 trillion in funds, meaning any decision it makes ripples the world over.