Freshfields Bruckhaus Deringer, Slaughter and and May and Maclay Murray & Spens have taken the lead roles on the merger of Aberdeen Asset Management and Standard Life.

The combination of the fund managers will create a company with around 9,000 employees, overseeing assets worth £660bn.

Freshfields and Maclays advised Aberdeen on the deal, which values Aberdeen at approximately £3.8bn. Aberdeen shareholders will own approximately 33% of the combined company, with Standard Life shareholders holding the remaining 67%.

Freshfields is fielding a team led by global financial institutions co-head Claire Wills (pictured) and London managing partner Julian Long.

The magic circle firm is working alongside Scots firm Maclays, which has a longstanding relationship with Aberdeen. The firm's team is being led by London corporate finance partner and financial services head Guy Norfolk, and Edinburgh corporate partner Brian Moore.

Slaughters, meanwhile, is advising long-term client Standard Life, with a team led by M&A head Roland Turnill and corporate finance partner Jonathan Marks.

Other Slaughters partners working on the deal include Paul Mudie (corporate), Jan Putnis and Nick Bonsall (financial regulation), David Ives (IP & IT), Sandeep Maudgil and Jonathan Fenn (pensions and employment), Gareth Miles (tax) and Stephen Powell (financing).

Lloyds Banking Group, which owns a 10% stake in Aberdeen, has also backed the merger.

Recent work Slaughters has handled for Standard Life includes advising on the £2.2bn sale of its Canadian business to Toronto-headquartered insurer Manulife in 2014, as well as its £1.75bn return to shareholders following the completion of the deal.

Maclays' relationship with Aberdeen dates back many years. In 2005, the firm took a lead role on its £265m acquisition of Deutsche Asset Management's UK arm, and also advised the fund manager in 2013 on its £650m acquisition of Scottish Widows Investment Partnership Group from Lloyds Banking Group.