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

Toronto Stock Exchange (13,009.93, down 156.15 points):

Encana Corp. (TSX:ECA). Oil and gas. Down 35 cents, or 4.79 per cent, to $6.96 on 14.1 million shares.

Telus Corp. (TSX:T). Communication services. Down $2.70, or 6.65 per cent, to $37.92 on 11 million shares.

First Quantum Minerals Ltd. (TSX:FM). Miner. Down 16 cents, or 3.97 per cent, to $3.87 on 7.2 million shares.

Pacific Exploration & Production Corp. (TSX:PRE). Oil and gas. Up 12 cents, or 6.98 per cent, to $1.84 on 6.8 million shares.

Teck Resources Ltd. (TSX:TCK.B). Miner. Down 31 cents, or 6.68 per cent, to $4.33 on 6.7 million shares.

Enbridge Inc. (TSX:ENB). Oil and gas. Down 11 cents, or 0.25 per cent, to $43.90 on 5.6 million shares.

Companies reporting major news:

TransCanada Corp. (TSX:TRP). Oil and gas. Down $1.61, or 3.34 per cent, to $46.56 on 4.5 million shares. TransCanada Corp. has filed an amended application for the Energy East pipeline project that raises the projected cost by nearly $4 billion. The Calgary-based company says the filing with the National Energy Board makes nearly 700 changes to the route in response to concerns about environmentally sensitive areas.

Shaw Communications Inc. (TSX:SJR.B). Telecommunications and media. Down $2.07, or 7.68 per cent, to $24.90 on 3.1 million shares. The $1.6-billion buyout of Wind Mobile by Shaw Communications puts the upstart wireless company one step closer to rolling out a high-speed LTE network and offering the latest Apple iPhones with its unlimited data plans. In announcing the deal Wednesday night, the Calgary-based cable provider said the acquisition of Wind gives it affordable entry into the wireless industry and an avenue for expanding Shaw’s customer base beyond Western Canada.