The divergence in views comes from the way in which market players and analysts understand the IPO and the role of Aramco in the Saudi economy.
Furthermore, to list in London, the proposed new "premium" listing category in London that Aramco needed, has been criticised by United Kingdom business leaders as liable to lead to "undue hands-on and politically-motivated" interference in sovereign-owned companies, potentially having a detrimental impact on the UK's wider corporate governance record. It will be the biggest stock market flotation in history and the market debut could value Saudi Aramco at $1.5 trillion, significantly below initial expectations of up to $2 trillion. Bank of America Merrill Lynch estimated anything from $1.2 trillion to $2.3 trillion; Goldman Sachs suggested $1.6 trillion to that same $2.3 trillion upper limit; HSBC put the range at $1.59 trillion to $2.1 trillion. However it did not give details on how much of the company would be sold, or when the listing would happen, while expert valuations of the company vary wildly from around $1.2 to $2.3 trillion.
The price at which all subscribers in the offering will purchase shares (the "Final Offer Price") will be determined at the end of the book-building period.
However, Aramco declined to comment. A deal over $25 billion would top the record-breaking one of Chinese e-commerce giant Alibaba in 2014.
"We knew it was a matter of time, so all the talk in the office was everybody save up, have some cash ready to go", said Nosaibah Alrajhi, 30, who founded and runs a financial services company.
By selling the oil company doesn't get profit, but it gets earnings from investments made in infrastructures as well.
Aramco is the world's largest oil and gas company by revenue with a net income of $111 billion in 2018.
This kicked off a campaign by stock exchanges in London, New York, Hong Kong and elsewhere to woo the authorities in Riyadh.
Norway's sovereign wealth fund, the largest in the world, has said it does not plan to invest in Aramco, a Norwegian official told AFP. She added 'concerns from a corporate governance viewpoint are wellflagged'.
"As a United Kingdom investor, I would view Aramco's lower yield as a negative", said Stephen Bailey, a fund manager at Liontrust."We prefer Royal Dutch Shell, given that it has a better investment profile and has fewer geopolitical risks associated with its stock". Other major institutional investors could well follow suit.
According to analysis sent to potential investors seen by Bloomberg, banks involved in the listing are finding it hard to pinpoint a value for Saudi Aramco. Yet the Saudi government has already conceded the company probably isn't worth the $2 trillion valuation Prince Mohammed has long advocated.