Shares of Chubb Corp (CB) spiked to finish Thursday's regular trading session sharply up after the company was acquired by peer ACE Ltd (ACE) in a mega transaction deal, making it TheStreet's Move of the Day. Chubb announced it is being bought by fellow luxury insurer ACE for $28.3 billion in cash and stock. Chubb holders will get $62.93 in cash and 0.6019 shares of ACE, which values the company at $124.13 a share. That price represents a 30% premium from Tuesday’s close. TheStreet's Jim Cramer, Portfolio Manager of the Action Alerts PLUS Charitable Trust Portfolio called the merger a 'monumental deal.' He called Chubb the most pristine insurer in the country. The combined company will be based in Zurich, but keep the bulk of its operations in New Jersey and also in Philadelphia, Penn. The companies expect to complete the deal during the first quarter of 2016. After the closing of the deal, Ace will own 70% of the company. Chubb shares finished the regular session up more than 26% on very heavy trading volume, making the top performing S&P 500 component on the day. TheStreet's Kurumi Fukushima reports in New York.