A growing mass of Research In Motion (RIM) investors backs calls for a sale or break-up of the firm that makes BlackBerry smartphone and wants a new, 'transformational leader' at its helm, according to a shareholder leading the drive for change.

Jaguar Financial Corp said on Tuesday holders of at least 8 per cent of the stock are behind its campaign for a shake-up, and that percentage could keep rising as it talks with more institutional shareholders about forcing a dialogue with the struggling Canadian company.

Shares of RIM rose more than 4 per cent after Jaguar's declaration of support.

The stock has been battered this year as the company steadily loses market share to devices made by Apple or powered by Google's Android software, raising questions about its direction and leadership.

'Everybody is in support of a sale of RIM or another value creative transaction like splitting the company into separate public companies - a network company, a device company and a patents company,' Jaguar chief executive Vic Alboini told Reuters on Tuesday.

Jaguar, a Canadian merchant bank that targets underperforming companies, wants RIM to hire a new chief executive to replace current co-CEOs Mike Lazaridis and Jim Balsillie, and to put itself up for sale, either as a whole or in parts.

With 8 per cent support Jaguar could demand a shareholders meeting, Alboini said, ratcheting up the pressure on RIM's board and management to address its demands. Alboini has a history of picking public fights with the boards of companies far larger than his own.

RIM said at its annual meeting in July that holders of more than 90 percent of its voting shares had backed the re-election of a slate of directors that includes the co-CEOs, who are also the two largest shareholders in the company.

RIM could not be reached for immediate comment on Tuesday.

The company's U.S.-listed stock sank a 52-week low of $19.29 a share on the Nasdaq on October 4, compared with a $70.54 high it touched in February.

Alboini said a reasonable range for RIM's stock valuation would be between $40 and $60/share, depending on the nature of any change at the company.

Any drastic change at RIM, with market capitalization of more than $12 billion, is seen running up against fierce opposition from Lazaridis and Balsillie.

Together the pair holds more than 10 percent of the stock and share a role as chairman of the board, enhancing their power over critical decision-making.

Even so, a series of profit warnings and the company's sluggish response to rapid change in the smartphone market have intensified pressure on  RIM's board to exert more influence over Balsillie and Lazaridis.

RIM's management is now attempting to execute a difficult transition to a new software system to operate its BlackBerry line at the same time as it loses market share in the corporate email market it once dominated.

In seeking to rally shareholders since early last month, Jaguar says RIM's leaders have lost their way in meeting the competitive challenge posed by Apple, Google, Microsoft, Samsung and HTC.

'It is time for RIM to bring in a transformational leader and a respected independent chairman,' said Alboini.

He said his firm had accumulated more shares of RIM since the stock price started to plunge, but he declined to say how many shares Jaguar now controls.

Alboini said Jaguar so far had spoken only to about 20 of the larger institutional holders, compared with the more than 1,000 investment managers listed by Thomson One as stockholders.

'We haven't adopted a call-center approach,' he said. 'It has been very highly targeted, but now that we've got the response, you know we are going to go out and see how many more we can get.'

Alboini said he had not been in contact with activist investor Carl Icahn and could not confirm speculation in recent weeks that Icahn might take a stake in RIM.

The stock rose nearly 4 percent in early trade on the Nasdaq and was up 4.1 percent at $24.17 per share  by 10:40 (14:40 GMT).

In 2009, Alboini played a crucial role in scuttling HudBay Mineral's friendly takeover of Lundin Mining, successfully appealing the Toronto Stock Exchange's approval of the transaction.

The all-stock deal between the base metal miners was unpopular with Hudbay shareholders because it would have involved the issuance of more stock, diluting the value of existing shares.-Reuters