Shenzhen Shares Suffer Worst Week Since December 1996 

China shares tumbled Friday, even as Beijing moves swiftly to try to plug losses, with the smaller Shenzhen index suffering its worst week since December 1996.

 
Aetna to Buy Humana for $37 Billion 

Aetna said it would buy Humana for $37 billion, following weeks of frenzied merger talks among large health insurers.

 
Germany's K+S Rebuffs Potash Takeover 

German salt and fertilizer company K+S AG rejected a takeover approach worth $8.75 billion by rival Potash Corp. of Saskatchewan, saying the proposal undervalued the company.