Aspiro soars on Tidal launch as star-struck investors miss Jay-Z deal

In what appeared to reflect investors clamouring too late for a piece of Aspiro's music streaming service Tidal, the shares were up 938 percent at 11 Swedish crowns just before trading was halted.

Some of the world's biggest music stars, including Kanye West and Madonna, were in New York on Monday to help publicise the launch of Tidal, which bills itself as the first service of its kind to be owned by artists.

The event is likely to have spurred interest in Aspiro's stock, lifting it to a level where buyers looked set to face losses of some 90 percent given the looming squeeze-out of the rump left after Jay-Z's $54 million acquisition of the company.

Those remaining shares will be bought at 1.05 crowns each.

"There are reasons to suppose that some have not noticed the communication around the bid," said Nasdaq OMX Stockholm spokesman Martin Hedensio.

Project Panther Bidco said this month it would start a compulsory purchase of the remaining shares and delist Aspiro from the Stockholm bourse. The last day of trading is April 2.

Hedensio said trading in the stock had been halted because of the big move, while the exchange checked whether there was any leak of information regarding the bid or any miscommunication. That was not the case, he said, adding there was no reason to cancel any trades.

The stock exchange reminded investors of the completed bid, saying trade in Aspiro shares would resume at 0940 GMT, but in a further twist prolonged the halt just before trading was due to restart.

Hedensio said this was because more time was needed to let the market digest the information, demonstrated by the fact there were still orders for Aspiro far above Jay Z's purchase price.

He added the exchange was calling brokers to make sure they were aware of the bid and the squeeze-out of remaining shares.

The exchange later said trading would resume at 1300 GMT, again stressing the upcoming delisting. "NASDAQ OMX Stockholm AB encourages all market participants to take measures to ensure that orders are reflecting the correct market value," it said.

($1 = 8.6527 Swedish crowns) (Additional reporting by Helena Soderpalm; Editing by David Holmes)