Can my boss force me to add them to a Facebook group?

[Rachel]

I'm in a group on Facebook made up of current and former employees at my former place of work. It's meant as a social group to maintain connections and friendships, with the occasional work-related announcement about a meeting time and that's about it.

My boss found out about the group and was upset that the group had members that were no longer employees and wanted access and administrative rights so they could see what was posted and control who was a member (they intended to remove all former staff members). I tried to explain the group wasn't really work related and I could make them one that was solely for work and current employees that they could administer but they said that the group was their property.

I'm just curious to know if they have any legal rights to gain access to this page or not.