Some of the most active companies traded Monday on the Toronto Stock Exchange:

Toronto Stock Exchange (15,445.22, down 9.82 points):

Kerr Mines Inc. (TSX:KER). Miner. Down 0.5 cents, or 16.67 per cent, to 2.5 cents on 7.1 million shares.

Talisman Energy Inc. (TSX:TLM). Oil and gas. Down eight cents, or 0.68 per cent, to $11.72 on 5.8 million shares.

Athabasca Oil Corp. (TSX:ATH). Oil and gas. Down 47 cents, or 6.83 per cent, to $6.41 on 5.7 million shares. The company sought to reassure investors that it’s working to close the $1.23-billion sale of its Dover oilsands stake to its Chinese partner amid reports of problems with the deal.

Bombardier Inc. (TSX:BBD.B). Aerospace. Down four cents, or 1.10 per cent, to $3.61 on 4.7 million shares

BlackBerry Ltd. (TSX:BB). Technology. Down 37 cents, or 3.33 per cent, to $10.75 on 2.7 million shares.

Spartan Energy Corp. (TSX:SPE). Oil and gas. Up two cents, or 0.50 per cent, to $4.06 on 2.4 million shares.

Companies reporting major news:

TransAlta Corp. (TSX:TA). Utilities. Down nine cents, or 0.71 per cent, to $12.60 on 503,008 shares. The power producer announced a $580-million plan to build, own and operate a new gas-fired power plant in Western Australia. The 150-megawatt power station will provide electricity to state-owned utility Horizon Power and to a subsidiary of Fortescue Metals Group, a major iron ore producer in the area.