Magic circle duo Clifford Chance (CC) and Slaughter and May are advising alongside a number of top US law firms on the $5.6bn (£4.3bn) purchase of UK insurance broker Jardine Lloyd Thompson Group (JLT) by US competitor Marsh & McLennan Companies.

Marsh & McLennan is seeking to bolster its speciality risk broking and global reinsurance business by acquiring the FTSE 200-listed UK company.

Linklaters advised Jardine Matheson, the 40% shareholder in JLT, with a team led by corporate partner James Inglis, alongside corporate partner Nick Rumsby.

Slaughters and US firm Wachtell Lipton Rosen & Katz are advising Marsh & McLennan on the takeover, with the magic circle firm's team consisting of senior partner Steve Cooke, corporate partner Richard Smith, competition partners Bertrand Louveaux and Lisa Wright, finance partner Ed Fife and financial regulation partner Nick Bonsall.

Partners Jonathan Fenn and Dan Schaffer also advised on pensions and employment matters, while Marsh & McLennan's internal legal team was led by executive vice-president and general counsel Peter Beshar.

The Wachtell team is being led by corporate partners Dan Neff and Greg Ostling.

CC, meanwhile, is advising JLT, with corporate partners Tim Lewis and Katherine Moir leading the firm's team with support from competition partner Greg Olsen and incentives partner Sonia Gilbert.

Other US firms with related roles on the deal include Davis Polk & Wardwell, which is advising Marsh & McLennan on the terms of a bridge-loan agreement, and Sullivan & Cromwell, which is representing Marsh & McLennan's financial adviser, Goldman Sachs.

The Sullivan team on the transaction includes London corporate partners Ben Perry and Jeremy Kutner, as well as City finance partner Presley Warner and New York corporate partner Stephen Kotran.

The Davis Polk team on the transaction included New York corporate partner and co-head of the global credit group James Florack and London banking partner Nick Benham.

Weil Gotshal & Manges is advising Goldman Sachs on providing committed bridge financing for MMC, with New York banking partner Morgan Bale leading the team.

Slaughters is also currently leading for insurance company Esure on its £1.2bn takeover bid by private equity firm Bain Capital, with Weil Gotshal & Manges advising the latter.