Responding to reports of employers seeking to gain access to people's Facebook profiles, Facebook warned employers not to demand the passwords of job applicants, saying that it's an invasion of privacy that opens companies to legal liabilities.

"If you are a Facebook user, you should never have to share your password, let anyone access your account, or do anything that might jeopardize the security of your account or violate the privacy of your friends," Erin Egan, Facebook chief privacy officer wrote in a blog post.

"We don't think employers should be asking prospective employees to provide their passwords because we don't think it's right the thing to do," he added. "But it also may cause problems for the employers that they are not anticipating. For example, if an employer sees on Facebook that someone is a member of a protected group (e.g. over a certain age, etc.) that employer may open themselves up to claims of discrimination if they don't hire that person."

Earlier this week, an Associated Press story documented cases of job applicants who are being asked, at the interview table, to reveal their Facebook passwords so their prospective employers can check their backgrounds.

"We'll take action to protect the privacy and security of our users, whether by engaging policymakers or, where appropriate, by initiating legal action, including by shutting down applications that abuse their privileges," Egan added.