RIYADH: Saudi Industrial Investment Group, or SIIG, said it has received the approval to acquire all shares of the National Petrochemical Co., known as Petrochem. In effect, Petrochem will be fully owned by SIIG and suspended from trading on the Saudi Stock Exchange beginning Monday, according to a bourse filing. As part of the buyout, SIIG will issue 304,800,000 ordinary shares with a nominal value of SR10 ($2.6) each. The acquisition transpired as Saudi Arabian energy companies are restructuring their operations in response to a market that has lost some of its demand.