Warren Buffett’s Berkshire Hathaway has become the third largest global reinsurer after its adverse development deal with AIG propelled the company into the top three for 2017.

According to data compiled by S&P Global Market Intelligence, Berkshire Hathaway’s reinsurance premiums written surged from $12.71bn in 2016 to $22.74bn last year, driven by the $10.2bn of premiums it collected for its $20bn adverse development cover for AIG and pushing it up three places in the latest rankings.

However, Berkshire’s top three spot is likely to be short-lived as the transaction was more of a one-off, meaning that Hannover Re and Scor will likely resume their positions as third and fourth largest respectively for 2018, having dropped down to fourth and fifth place last year.

German heavyweight Munich Re remains the industry’s largest reinsurer after writing $35.67bn of reinsurance premiums in 2017 and Swiss Re in second place with $29.95bn of premiums.

S&P highlighted that until last year, the European big four reinsurers – Munich Re, Swiss Re, Hannover Re and Scor – had held their positions since at least 2008.

Meanwhile, S&P noted that upon completion of Axa’s $15.3bn acquisition of XL, the combined entity will likely have a strong position in the top 10, with 2017 pro forma reinsurance numbers of $11.75bn ranking the collective business in seventh place.

This is just behind Lloyd’s, which took sixth position in 2017 after its reinsurance premiums grew by 6.8 percent year-on-year to $13.61bn.