Lagos — MTN Group has been promising to list its Nigerian business on the Lagos stock exchange for almost three years, yet it took just 16 minutes for the mobile-phone giant to cause a sensation.

After a lengthy ceremony of speeches, congratulations and rounds of applause delayed the start of trading for more than half an hour, it looked as though MTN Nigeria Communications   may not trade at all with the market due to close for the day at 2.30 pm. The listing finally took place at 2.14 pm local time, leaving only a brief window before traders knocked off for the day.

The reaction was instant. The stock jumped 10% to 99 naira from the listing price announced the previous day — the maximum possible move under Nigeria Stock Exchange rules. That values the wireless carrier at 2-trillion naira ($5.6bn), making MTN Nigeria the second-biggest company on the NSE. The All-Share index acted accordingly, turning a loss for the day into a slight gain.

The reverse was significant because Nigerian stocks have had a torrid time of late — they are  down 9.5% this year. That is  the fourth-worst performance globally, according to data compiled by Bloomberg. They were on track for their ninth straight day of losses until MTN Nigeria’s shares were listed, yet ended the day up 0.5%, the best showing in almost a month.

There may be even bigger moves to come. MTN, Africa’s biggest wireless carrier, has arranged to list the stock in two stages. The first, which took place Thursday, allows Nigerian investors who previously bought and sold their shares over the counter to trade them publicly. At some yet-to-be-determined date, MTN will add to the free float by selling part of its 79% stake.

It will not be before MTN resolves an ongoing dispute with the Nigerian attorney-general over the alleged nonpayment of $2bn in back taxes, MTN CFO Ralph Mupita said by phone. The end result will be that MTN Nigeria will have a free float of about 35%, with the Johannesburg-based parent maintaining majority control, he said.

“We will soon come back for the IPO,” MTN Nigeria chair Pascal Dozie told a full house of reporters, brokers and dignitaries on the 9th floor of the Nigerian Stock Exchange.

With assistance from Renee Bonorchis and Loni Prinsloo.