Roughly a month after saying it would explore its strategic options, BlackBerry Ltd. announced Monday it has agreed to sell itself to a consortium led by its largest investor, Canadian insurance company Fairfax Financial Holdings, in a deal worth $4.7 billion.

The proposed deal is for the 90 percent of the company that Fairfax Financial—which is being represented by Shearman & Sterling and Canadian firm McCarthy Tétrault—does not already own.