Nortel Networks

Northern Electric, founded in 1895, became Nortel Networks, the telecommunications-equipment giant that anchored Canada’s economy. At its 2000 dot-com peak it was worth roughly $250 billion and accounted for about a third of the entire value of the Toronto Stock Exchange. The crash gutted its market, and an accounting scandal in the mid-2000s forced restatements and executive firings. Burdened by debt and unable to recover, Nortel filed for bankruptcy protection in January 2009 and was broken up. Its prized patent portfolio sold for $4.5 billion in 2011 to a consortium of rivals.