Baker McKenzie and Freshfields Bruckhaus Deringer have taken the lead roles on Japanese conglomerate Hitachi's $6.4bn (£5.1bn) acquisition of a power grid business from Swiss engineering group ABB.

The deal, expected to close in the first half of 2020, will be Hitachi's largest-ever acquisition and make the Japanese conglomerate the world's second-largest heavy electrical-equipment maker by revenue, behind General Electric, according to the Nikkei Asian Review.

Hitachi will first acquire an 80.1% stake in the power grids unit, and retain the option to acquire the remaining stake – making the unit a wholly owned subsidiary of the Japanese conglomerate. The deal values the power grids business at $11bn (£8.7bn).

Baker McKenzie London partners David Allen and Jannan Crozier are advising Hitachi, supported by Tokyo partners Akifusa Takada and Yutaka Kimura.

The global legal giant previously advised Hitachi subsidiaries, including power-tools maker Hitachi Koki on a $180m acquisition of German power-tools maker Metabo in 2016; and management consultancy Hitachi Consulting on its acquisition of Singapore-based technology consultancy Stone Apple Solutions in 2014.

Freshfields London partners Piers Prichard Jones and Stephen Hewes are advising ABB. Jones previously advised the Swiss company on a $1.3bn acquisition of British power-equipment maker Chloride Group in 2010.

The Hitachi-ABB deal comes as a wave of Japanese companies are making acquisitions abroad, such as drugmaker Takeda Pharmaceutical's $62bn acquisition of London-listed Shire, which is expected to close on 8 January.

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