INSURANCE

IPC Holdings Offers to Buy Tempest for $943 Million: The bid is an attempt to thwart a merger agreement between Tempest Reinsurance Co. and Ace Ltd. IPC Holdings Ltd., which provides property reinsurance, said its offer is worth $180 a share in cash and stock, or about 10% more than Ace’s offer. Shareholders of Tempest, which is a closely held company, are scheduled to vote on the Ace proposal June 19. The competing bid reflects growing demand for reinsurance--the way insurers protect themselves from exposure to risk from policy claims. The 10 most costly U.S. disasters have struck in the last seven years, and Bermuda, where IPC, Ace and Tempest are based, has turned itself into a haven for reinsurers seeking minimal regulation.