(Bloomberg) –The world’s biggest initial public offering turned out even bigger than initially thought.

The final amount raised by Saudi Aramco’s sale totaled $29.4 billion as Goldman Sachs Group Inc., one of the underwriters of the world’s biggest IPO, exercised the option to place some shares that were initially separated to avoid price swings, according to a statement. It said 450 million additional shares were placed at 32 riyals ($8.53) with investors during the book-building process.

According to the terms of the offering, the bank could buy the additional shares during the stabilization period that ended Jan. 9 and give support to the stock, but no such transactions were undertaken during that interval. The IPO relied heavily on individuals and high-net worth investors and funds from the Gulf, with the Saudi government institutions investing almost $2.3 billion into the offering.

Aramco retreated 0.6% to 34.80 riyals in Riyadh on Sunday, extending drop of 0.4% for the week ended Jan. 9. Still, the stock is trading 8.8% higher than the IPO price.

–With assistance from Matthew Martin and Paul Wallace.