Shares of Serono slid as the Swiss drug developer announced that even though it's been in talks to be acquired, there's no guarantee of a deal. "The process is ongoing," said the statement. But after bidding up Serono shares in anticipation of a buyout offer, that's not what investors wanted to hear. GlaxoSmithKline, Novartis and Pfizer have all reportedly been at the bargaining table with Serono, which also announced a $106 million loss for last year. The loss was due primarily to a big fine, but analysts were also disturbed by Serono's drug sales numbers for the fourth quarter, which were flat.

- read this report from The Financial Times for more