On July 17, 2014, Liberty Mutual Insurance reached a definitive agreement with National Indemnity Company, a subsidiary of Berkshire Hathaway Inc., on a combined aggregate adverse development cover for substantially all of Liberty Mutual Insurance’s U.S. workers compensation, asbestos and environmental liabilities, attaching at approximately $12.5 billion of combined aggregate reserves with an aggregate limit of $6.5 billion.

At the closing of this transaction, but effective as of January 1, 2014, Liberty Mutual Insurance ceded approximately $3.3 billion of existing liabilities under a retroactive reinsurance agreement. NICO will provide approximately $3.2 billion of additional aggregate adverse development cover. Liberty Mutual Insurance paid NICO total consideration of approximately $3.0 billion.

The agreement covers Liberty Mutual Insurance’s potentially volatile U.S. asbestos and environmental liabilities arising under policies of insurance and reinsurance with effective dates before January 1, 2005, as well as Commercial Insurance’s workers compensation liabilities as respects injuries or accidents occurring before January 1, 2014. NICO will assume responsibility for claims handling related to Liberty Mutual Insurance’s asbestos and environmental claims. Liberty Mutual Insurance will continue to handle all workers compensation claims.

“We believe that this agreement further strengthens our financial position as it eliminates a substantial source of uncertainty in these liabilities and allows us to focus on execution in our core businesses,” said David H. Long, Liberty Mutual Insurance Chairman and Chief Executive Officer. Workers’ compensation has challenged U.S. insurers amid climbing medical costs and low interest rates that make it hard for carriers to generate investment income from the premiums they hold. The industry has posted underwriting losses in the segment every year since 2007, according to data from the National Council on Compensation Insurance Inc

This transaction will be accounted for as retroactive reinsurance in Liberty Mutual Insurance’s GAAP consolidated financial statements and results in a pre-tax loss of approximately $130 million as of the effective date, which will be included in third quarter results. Standard and Poor’s raised Liberty Mutual’s credit rating one grade to BBB, two levels above junk, after the announcement. The deal “largely mitigates” the insurer’s risk of having to add to reserves and reduces earnings volatility, the ratings company said in a statement.

As chairman and CEO, Buffett, 83, fueled Berkshire’s growth over the last five decades by investing insurance premiums in stocks and takeovers. The company’s dozens of operating businesses now span the transportation, energy, manufacturing and retail industries.