The coal explorer said the shares were subject to a voluntary escrow restriction for a period of 12 months.
Korea’s East-West Power Company has signed similar agreements to receive almost 10 million shares, but the shares have not yet been allotted.
Both Kores Australia and East-West Power were existing shareholders of Cockatoo before deciding to up their stakes.
Kores Australia is a South Korean government-owned subsidiary of Korea Resources Corporation.