Alcoa (AA +4% to $18) continues to climb amid rumors that Rio Tinto (RIO -1.6%) is preparing a...

|By:, SA News Editor

Alcoa (AA +4% to $18) continues to climb amid rumors that Rio Tinto (RIO -1.6%) is preparing a $25.50/share bid for the aluminum giant. Investors are loading up May and June calls at an $18 strike price. It's not the first time traders have talked about Rio buying Alcoa, but existing ownership of Alcan might raise antitrust issues.