What are the defences available to a social networking site where an individual has posted a defamatory comment about their employer?

If the social networking site can show that it did not know, and had no reason to believe, that it had caused or contributed to the publication of a defamatory statement, it may have a defence available to it of "innocent dissemination" (s.1 of the Defamation Act 1996) if, once notified, it acts expeditiously to remove the material.

Section 5 of the Defamation Act 2013 provides a further defence for website operators that host user-generated content where the site can demonstrate that it was not responsible for posting the content and that it has complied with the procedure set out in the Defamation (Operators of Websites) Regulations 2013 (SI 2013/3028). The Government has published guidance on s.5 and the detailed procedural requirements contained in the Regulations.