Swiss Re, the biggest underwriter of the destroyed New York World Trade Center, will not be forced to make two separate payouts, a US court has ruled.
Rebuilding the site could cost $12bn
The giant insurer, which alone provided 25% of the cover for the twin towers, will pay no more than $880m (£497m).
The decision follows a court ruling that the September 11 attacks should count as one act, not two as the building's developer had claimed.
The developer, Larry Silverstein, had asked for twice the £3.5bn sum insured.
The judgement sent Swiss Re's shares up by 2.5%, since analysts had been braced for a far larger payout.
The court decision, which is likely to be mirrored in cases involving all the building's insurers, will restrict the amount of capital available to rebuild the site.
Current plans for the project are estimated to cost up to $12bn.