Whitehaven’s largest shareholder Nathan Tinkler

Whitehaven’s largest shareholder Nathan Tinkler

Martyn Rushby/Aston Resources Ltd. via Bloomberg

Nathan Tinkler, former chairman of Aston Resources Ltd., is seen in this Nov. 16, 2011 photo. Tinkler, a former electrician who became Whitehaven’s largest shareholder after the company acquired his Aston Resources Ltd., offered to buy the company in July.