Mr. Heal said that Aramco faced many risks, including the geopolitical dangers in the Middle East, demonstrated by the aerial attacks in September on two major Aramco production facilities, and the potential for declining demand for oil because of concerns about climate change.

Indeed, the prospectus acknowledges that “terrorism and armed conflict may materially and adversely affect” Aramco and its share price in the future.

The prospectus details a series of recent attacks, including the ones in September, and concludes that others could have a serious impact on the company’s “business, financial position and results of operations” as well as discourage investors from buying the shares.

The company also acknowledged that growth in demand for oil has been slower than global economic growth in recent years because of factors like gains in fuel efficiency and the emergence of alternative energy sources like wind and solar and electric vehicles.

Growth in demand for oil is likely to level off by 2035, according to the document, but it adds that the market share of low-cost producers like Saudi Arabia is likely to increase. The kingdom, the document forecasts, will probably be able to produce increasing amounts of oil until 2050.

For investors, Mr. Heal said, the most immediate threat could be rising oil supplies. A surge in oil supplies from the United States as well as other producers like Brazil, Canada, Norway and Guyana may drive prices down. In that case, the company might struggle to earn sufficient profits to pay the substantial dividends of $75 billion a year that it has promised investors.

“Profits could be lower than we think,” Mr. Heal said.

Aramco said in the prospectus that the company “is committed to delivering sustainable and growing dividends to its shareholders” through ups and downs in oil prices. The company even says the government is prepared to forgo a portion of its dividends so that nongovernment shareholders receive payouts based on the $75 billion total.