Alcoa's current bid, according to regulatory filings, includes $22 a share in cash and 0.9418 of an Alcoa common share for each Alcan share.
Alcoa shares shot up in late June after the company said it would cut its aluminum production by 25 percent.
Shares of Alumax jumped $10.3125, or more than 28 percent, to $47, while Alcoa shares fell 18.75 cents, to $71.4375.
Alcoa said it would pay $50 a share in cash for half of the shares of the Atlanta-based Alumax and would exchange 0.6975 Alcoa share for each of the remaining Alumax shares.
Alcoa shares fell $1.6875, to $65.1875, yesterday, and Reynolds was off $2.6875, to $65.5625.
On the New York Stock Exchange, Alcoa shares rose $1 to $75.875 yesterday.
Alcoa shares rose $2.9375, or 4.4 percent, to $69.375.
Alcoa shares lost $3.125 each, closing at $64.75.
Even were the Bush tax cut more equitable in offering relief to Americans with fewer Alcoa shares than his treasury secretary, it's too little and too late to serve as a stimulant.
The bid offers Alcan shareholders $58.60 a share in cash plus 0.4108 of an Alcoa share, representing a 20 percent premium over Friday's closing price.
