YouGov, a research and data group, is acquiring GfK's global consumer panels division for £300m.
The acquisition is expected to accelerate YouGov's strategy and is likely to be well-received by the market.
The deal comes just months after YouGov appointed a new CEO from
Facebook-owner Meta.
The company's biggest-ever acquisition will likely involve raising tens of millions of pounds from institutional investors.
YouGov was founded in 2000 and listed on the London stock market in 2005.