2 Founders of BlackBerry Weighing a Takeover Offer OTTAWA - The two men who founded the company that became BlackBerry may now try to save it. In a regulatory filing on Thursday, Mike Lazaridis and Douglas Fregin said that they were considering a bid for the 92 percent of the company that they do not own. They also said they had hired Goldman Sachs and Centerview Partners as advisers. Their potential bid joins a growing list of expressions of interest in the company, which recently reported a $1 billion quarterly loss caused by the market's rejection of new smartphones that were supposed to revive BlackBerry's prominence. Fairfax Financial Holdings of Toronto has made a conditional, nonbinding offer to buy the 90 percent of BlackBerry shares it does not own for $9 each. That would value the company at about $4.7 billion. Many investors are skeptical about Fairfax's ability to finance that proposal by bringing in other investors and borrowing billions of dollars. Similar questions would apply to any rival offer from Mr. Lazaridis and Mr. Fregin, who are not working with Fairfax at the moment, according to a person briefed on the matter. Cerberus Capital Management, a private equity firm known for its investments in distressed companies, has been pursuing a nondisclosure agreement with BlackBerry that would give it access to confidential data, a person briefed on those discussions has said. In addition, several media reports have indicated that BlackBerry has been sounding out other technology companies about their interest in buying at least part of its business or assets. It is not clear whether any of them will bid. A spokesman for Mr. Lazaridis declined to comment. Adam Emery , a spokesman for BlackBerry, declined to specifically comment on Thursday's filing but said that the company "is conducting a robust and thorough review of strategic alternatives." Mr. Lazaridis has already been casting about for potential partners, having approached the likes of the Blackstone Group and the Carlyle Group, people briefed on the matter have said. Talks with Blackstone have cooled off, while talks with Carlyle have not advanced beyond a preliminary stage, according to those people. Shares of BlackBerry closed up just over 1 percent on Nasdaq, but at $8.20 a share, it remained below Fairfax's tentative $9-a-share offer. Mr. Fregin and Mr. Lazaridis have been friends since attending elementary school in Windsor, Ontario. Mr. Fregin abandoned his engineering studies at the University of Windsor to join Mr. Lazaridis in Waterloo, Ontario, where he was studying, to start Research in Motion in 1984. The company changed its name to BlackBerry this year. It was Mr. Lazaridis, however, who would become the public face of the company after its successful move into the smartphone business, along with Jim Balsillie, with whom he shared the title of chief executive and chairman until January 2012. Mr. Fregin worked quietly as the company's vice president for operations until 2007. After Mr. Lazaridis stepped down from control at BlackBerry, the two men formed Quantum Valley Investments to invest in quantum-computing technologies. There has been considerable speculation that Mr. Lazaridis would become involved in some kind of a bid. It includes the possibility that he would take over the company's handset business, which many analysts now say is virtually worthless, while other investors would acquire BlackBerry's software and services businesses. The viability of the phone business aside, such a separation might prove difficult. In recent days, BlackBerry has been acting like a company preparing itself for sale, including settling some outstanding patent litigation. As part of a broad downsizing, BlackBerry said on Thursday that it would close an office in Halifax, Nova Scotia, with the potential loss of 350 jobs, mostly in technical support. The company would be required to repay about $2 million in government job grants.