The Iraqi mobile phone operator Asiacell has raised $1.3bn (£828m) on the stock market.
The flotation on the Iraq Stock Exchange (ISE) was seen as a test of investors' confidence in the country.
About two-thirds of the shares were bought by foreign investors. They will begin trading on the exchange on Monday morning.
Asiacell sold 25% of its shares in the offering, valuing the whole company at over $5bn.
The offering doubled the market capitalisation of the ISE.
According to a local broker, the main buyer of the shares was the Kuwaiti company, Qtel, which already owns almost 54% of Asiacell.
Some local traders avoided the listing, saying the shares were overpriced.
Asiacell was forced to sell some of its shares on the ISE as part of the terms of its licence from the government.
Its local rivals Zain Iraq, which is a subsidiary of Kuwait's Zain, and Korek, which is owned by France Telecom, will have to follow suit.