In February 2008, UAL Corporation and Continental Airlines began the advanced stages of merger talks and were expected to announce their decision in the immediate aftermath of a definitive merger agreement between rival Delta Air Lines and Northwest Airlines. The timing of the events was notable because Northwest's golden shares in Continental (that gave Northwest veto authority against any merger involving Continental) could be redeemed, freeing Continental to pursue a marriage with United. On April 27, 2008, Continental broke off merger negotiations with United and stated it was going to stand alone. Despite ending merger talks, Continental announced that it would join United in the Star Alliance.