Swiss reinsurer Converium Holding on Friday urged shareholders to reject a $800 million hostile takeover from French rival SCOR.
"Converium's board of directors urges its shareholders to reject SCOR's offer, believing it to fundamentally undervalue the company's franchise and growth prospects," Converium said in a statement.
SCOR earlier this month offered to buy rival Converium in a deal that values the entire Swiss company at about $2.56 billion.
The offer, which was officially published in the Swiss press, matches an unofficial notification of interest SCOR issued in February when it said it would offer 21.25 Swiss francs ($17.42) per Converium share.
SCOR, which already owns more than 32% of the Swiss company's shares, said it would set a deadline of May 22 to acquire at least 50%-plus-one Converium shares.
Converium shares added 0.9% to 22.3 Swiss francs ($18.29) in trading in Zurich.