Institutional demand for Saudi Aramco's shares reached 189 billion Saudi riyals (Dh185bn) in the first 17 days of book-building, according to lead arrangers Samba Capital, NCB Capital and HSBC Saudi Arabia.
Investors subscribed to a total of 5,914,705,682 shares at the top end of its 30-32 riyals price range.
The company, which accounts for one in every eight barrel of oil produced, is set to float 1.5 per cent of its shares on the Saudi stock exchange, Tadawul, next week.
Book building among institutional investors concludes at 5pm Saudi time today, with the company expected to price its shares tomorrow.
Retail subscriptions for the IPO closed on Friday, reaching 47bn riyals or 1,481,613,280 shares. Retail and institutional bids now stand at about 236bn riyals, around 2.5 times the 96bn riyals that would be raised if a float took place at 32 riyals per share. This would give the company an overall valuation of about $1.7 trillion (Dh6.24n).
The IPO will be a watershed both for Saudi Arabia's stock exchange and for wider capital markets in the region.
"The IPO proceeds of $24-25.6bn (Dh88-Dh94bn) to be raised by Saudi Aramco is easily set to be higher than the combined IPO proceeds of the GCC region witnessed in the recent past," an analysts' note by Kamco Research issued on Wednesday said.
"We believe that the Aramco IPO provides a significant opportunity for Saudi Arabia and the overall MENA region in attracting foreign capital in the form of both institutional money as well as FDI (foreign direct investment)," it added, stating that the process also opened the door for further privatisations in the kingdom.
In the near term, the listing is expected to attract inflows of foreign funds as global index compilers such as MSCI and FTSE Russell include Aramco in their indices. Around $4bn to $5bn can be expected to flow in Saudi equities from funds that track these indexes, the Kamco Research note said.
Saudi Aramco is estimated to take up a share of 9.1 per cent to 9.7 per cent of the Tadawul All-Share index, according to estimates from Al Rajhi Bank.
The Saudi stock exchange — largest in the Arab world — issued new market index rules on Monday, limiting the influence of any one firm over the benchmark.