is this legal to make an employee sign a paper stating she can not talk about work on facebook?

[Keith]

my girlfriend's employer made her sign a paper before she got her check saying she will not talk about her employment on facebook, is this not a infringement on her freedom of speech?

[Ashley D]

its a confidentiality issue. they don't want their business on facebook, so they have a right to restrict it.

all the answers so far are great. if something happens on facebook that would affect the business, they have every right to do something about it