Investors on Tuesday increased their bets that other bidders would emerge for Bear Stearns or that JPMorgan Chase would be forced to improve its offer, driving shares in the beleaguered investment bank to nearly three times the price at which JPMorgan agreed to take it over.

Investors were betting that opposition from some shareholders, such as Joseph Lewis, the UK-born billionaire whose stake in Bear is believed to be about 9 per cent, and some of Bear’s employees – who own about a third of the shares – could force the takeover price to be raised. JPMorgan agreed to pay $2 a share but Bear’s stock closed on Tuesday at $5.91, up 23 per cent, after trading as high as $8.50 during the day.