Dorchester Pacific says approximately 134 million of the 150 million options on issue have been exercised and will convert into ordinary shares.
Chief executive Paul Byrnes says the number exercised was higher than expected.
He says the company is now working with major shareholders to see if some of their holdings can be made available as a small secondary pool to go towards meeting placement demand.
Dorchester says the total of new shares issued through the exercise of options and the share placement will be limited to 150 million.
Shares will be issued on 17 June.