Jack Ong Tong Hai, CEO of Cosmosteel Holdings, has again bought shares in the open market to increase his stake.

On May 22, Ong paid 22 cents each for 500,000 shares, bringing his total stake to more than 43.9 million shares, equivalent to 16.81%, up from 16.62% earlier.

Ong had on May 20 paid nearly 22 cents each for 5.55 million shares.

Ong's actions came after a group of investors on May 15 launched a takeover offer for the company at 20 cents each.

This group of investors include a subsidiary of Cosmosteel's single largest shareholder Hanwa Co, a Tokyo-listed trader of steel and other materials which now owns 31.61% of Cosmosteel.

Cosmosteel closed at 22 cents on May 22, down 4.35%.