If the BFS comes out without an offer, Teck's strategy may be to accumulate shares on the open market if their intention is a buyout to follow soon after. They will no longer be privelege to insider info. as it will have been made public. They can legally buy up to 10% of the float ( or about 40M shares ) before they declare their intentions. Nevertheless, this much buying pressure in a short span can really drive up the sp to say $3 or $4/sh and then a $6 or $7 buyout offer will not look as bad for their shareholders. Or they may not want to risk a competitor grabbing up shares on the open market and make an offer concurrent with the BFS release.