Shares of Czech anti-virus provider Avast fall after allegations of data harvesting

Shares of Czech anti-virus giant Avast fell by up to 9 percent in one day on the London stock exchange, following news that the company’s browser extensions may be harvesting users' data which is later sold to supply marketers, news site iHNed.cz reports. Company shares valued at around GBP 5.3 billion have fallen by a further 5 percent on both the London and Prague stock exchanges since the stock exchanges opened on Wednesday, according to iHNed.cz.

The issue was put under the spotlight after major web browsers Mozilla, Opera and Google removed Avast and AVG extensions because they were suspected of collecting user data and sending it on to Avast servers.

Avast says in its defence that users were able to unsubscribe from the data sending function and reassured that personal information including names, email addresses and contact details are not harvested.