Berrymans and Lace Mawer have merged to create a national defence insurance law firm, to be called Berrymans Lace Mawer.
With 250 fee earners, 80 of them partners, it is by far the largest insurance law firm in the country, and one of the 30 largest law firms overall.
The motivation to create the practice was demand from the large clients of insurers to have one law practice dealing with their cases, rather than a panel of firms.
Berrymans Lace Mawer has two London offices, one specialises in shipping, reinsurance and Lloyd's, and other offices in Birmingham, Leeds, Liverpool, Manchester, Southampton and in Dubai. It is looking at opening in Bristol and Newcastle.
The firm will be run by four partners: Martin Bruffell and Paul Taylor from Berrymans and Stephen Cheshire and Nigel Roden from Lace Mawer. Although it is comparable in size to Davies Arnold Cooper and smaller than Herbert Smith, both those firms have major practices in other areas.
At Berrymans, 85 per cent of the business is insurance and at Lace Mawer 75 per cent.
The merger is part of the continuing shake-up of defence insurance law, caused initially by the reduction in the size of panels, and also by the merger of Royal (one of Lace Mawer's biggest clients) and Sun Alliance (Berryman's biggest).
Roden added that the firm would evolve a unified style through training, rather than by moving people between offices.