Berkshire Hathaway is seeking up to $1 billion in damages from Swiss Re, the reinsurer it aided during the financial crisis, reports Financial Times.

It says “the dispute relates to losses Berkshire has endured since providing what Swiss Re calls “retrocession”—reinsurance for reinsurance—to the Zurich-based company’s US life and health arm.”

Berkshire sustained a $642 million pre-tax underwriting loss arising from the arrangement last year.

Read more on why Buffett is taking action.

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