So they hold 75mill of the total 484,538,583 shares per:
http://markets.businessday.com.au/apps/qt/quote.ac;jsessionid=080EF4C1684485ACDADD771AE62E416A?code=aop§ion=summary&submit=Go&submit=
So they control aprox 15.5% of the issued shares. Not taking into account tails/heads ratio.
That seems to be a nice ratio, if the figures and calculation is correct.