Nearly half of employers have banned access to Facebook in the workplace, research by Sophos has found.

The IT security firm, which polled 600 workers, revealed that up to 43% of workers said their employers had blocked access to the popular social network.

An additional 7% of respondents said access to Facebook was restricted and only those with a business requirement were allowed to visit the site.

However, 50% said that their company did not ban access to the MySpace rival, with 8% citing fear of employee backlash as the reason behind the decision.

Last week ComScore reported that Facebook was the UK’s third most visited social network after Bebo and MySpace, with 7.6m unique visitors in July 2007.

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