France's Schneider Electric is to buy industrial software firm Invensys for a 3.4 billion pound ($5.2 billion).
Schneider, which has 140,000 employees, has signaled plans to offload non-core divisions within Invensys, which develops technology for oil refineries and other sectors. Invensys has 1,100 employees in Britain and the United States.
The deal must still be approved by shareholders.
Invensys chair Nigel Rudd says there was a "strong strategic fit" between the two companies. Jean-Pascal Tricoire, chairman and chief executive of Schneider said the combined business will provide new and larger growth opportunities for employees and customers.
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