Avast has acquired a majority stake in AVG Technologies, creating a security behemoth with over 400 million users globally.
The two firms will combine to operate as a single entity from next week and plans are under way for AVG to delist from the Stock Exchange as Avast is a privately held company.
Vince Steckler has been announced as the new CEO, overseeing more than $700m (£539m) in revenue for the merged firm, and AVG's chief executive Gary Kovacs will leave, but act on a consulting basis during the transition period.
Steckler said in a statement: "The combined company now has over 400 million users - more than 40 per cent of the world's consumer PCs outside China and the largest consumer security installed base in the world. If it were a country, we would have the third largest population in the world.
"The US is now our number one market, with 58 million users. We truly have global reach and are proud to be the most popular choice for security in the world.
"We now have the technical breadth to provide superior protection for our customers. For example, our combined threat labs will have teams dedicated to emerging threats affecting consumers. These include social engineering threats, which are commonly used to target IoT devices, and ransomware, which we are fighting with machine learning technology. We believe we are now better equipped than ever to outsmart those who want to do harm to people online."
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