Investors in niche financial bonds that cover insurers against huge natural disasters are on alert for future events that could force them to pay out after the powerful tornado that struck the U.S. on Monday, brokers and fund managers said.

Investors in niche financial bonds that cover insurers against huge natural disasters are on alert for future events that could force them to pay out after the powerful tornado that struck the U.S. on Monday, brokers and fund managers said.

Allstate, the largest publicly traded U.S home and auto insurer, has returned to the catastrophe bond market with a $250 million offering, five years after investors lost millions of dollars on a previous issue due to the collapse of Lehman Brothers.

Munich Re has sold a $500 million catastrophe bond to protect two North Carolina underwriting associations against hurricane losses, as insurers increasingly choose to cover risks with bonds rather than buying traditional reinsurance.

Munich Re has sold a $500 million catastrophe bond to protect two North Carolina underwriting associations against hurricane losses, as insurers increasingly choose to cover risks with bonds rather than buying traditional reinsurance.

Strong demand for a $270 million catastrophe bond allowed its issuer, U.S. Nationwide Mutual Insurance Co, to price it more cheaply than expected, leaving investors looking for a higher return from future issues.

Strong demand for a $270 million catastrophe bond allowed its issuer, U.S. Nationwide Mutual Insurance Co, to price it more cheaply than expected, leaving investors looking for a higher return from future issues.

Munich Re is marketing a new catastrophe bond through a special purpose vehicle set up to protect two North Carolina underwriting associations against $200 million of hurricane losses in the region.