Research In Motion, maker of the BlackBerry smartphone, rose 8 per cent after a report that Samsung Electronics may be interested in buying the company.
RIM advanced to $17.47 at the close in New York. Samsung may be interested in buying RIM, and no deal has been made because Waterloo, Ontario-based RIM is asking too much, the blog BGR reported.
An acquisition of RIM, whose stock fell 75 per cent last year amid market-share losses, would give Samsung an operating system that would help it differentiate from competition as it seeks to stay ahead of Apple.
Samsung now makes phones based on Google's Android software and Microsoft's Windows Phone, operating systems also used by rivals such as HTC Corp.
"This has been speculated before, and it does have logic to it in the sense that Samsung has no viable high-end smartphone operating system, and increasingly reselling Android or Windows Phone is being viewed as a commodity business," said Tavis McCourt, a Morgan Keegan analyst in Nashville, Tennessee.
Tenille Kennedy, a spokeswoman for RIM, and Brett White, a spokesman for Samsung, both declined to comment.
At about $9.2 billion, RIM's market capitalisation is a fraction of Samsung's $133 billion.
Short of an acquisition, RIM could strike a technology-licensing deal with Samsung, McCourt said.
RIM's new BlackBerry models with touch screens and upgraded browsers, introduced last year, have failed to stop customers from opting for the iPhone and Android devices.
The slump in the company's share price prompted investment firm Jaguar Financial to call for RIM to split into separate companies, seek a buyer and shake up its management.
RIM's stock has jumped at least 5 per cent more than 10 times since the beginning of August on speculation a decline in its valuation will invite a takeover.
The company's share of US mobile-phone subscribers in the three months through November dropped to 6.5 per cent from 7.1 per cent in the previous quarter, according to research firm ComScore.
Samsung, based in Suwon, South Korea, increased to 25.6 per cent from 25.3 per cent, and Apple gained 1.4 percentage point to 11.2 per cent.
Samsung said this week it was seeking to raise money through its first overseas bonds since 1997.
The company, a supplier to Apple, plans to expand production capacity at a Texas factory making chips used in mobile devices.