Have a gripe about your working conditions?

You'd be wise not to air it on Facebook or Twitter, although if you do, federal labor regulators have your back -- more or less.

While businesses continue to wrestle with the online realm -- trying to craft employee social media policies that will protect their brand and withstand future court challenges -- federal regulators now have a track record on the issue, ordering employers to stand down when it comes to workplace policies that broadly forbid employees' online activities and conversations.

Last week, The New York Times reported on a series of federal rulings and advisories that have overturned firings, or challenged codes of conduct that "discourage comments that paint [companies] in a negative light."

Those policies run afoul of the National Labor Relations Board's position, which says "workers have a right to discuss work conditions freely and without fear of retribution, whether the discussion takes place at the office or on Facebook," the Times reported. In several recent cases, the NLRB has overturned firings that were rooted in violations of those too-broad social media policies.

"They're leaving a trail of bread crumbs here to tell us what they're looking for. Employers have plenty of clues," said Maria Greco Danaher, employment law attorney and a shareholder in the Pittsburgh office of Atlanta-based Ogletree Deakins.

Generally, the NLRB has been protecting employees who discuss their jobs, workplace issues or working conditions online, in a constructive or "concerted" way.

Those same protections may not be extended to lone employees making rogue comments on the Internet -- the NLRB upheld the firing of a police reporter at The Arizona Daily Star and a bartender in Illinois, both of whom made offensive online postings that were only vaguely job-related.

The bartender in question called his customers "rednecks" and said he hoped they choked on glass as they drove home drunk, while the reporter joked that his job would be more exciting if only there were more homicides to write about, according to the Times.

The rulings follow recent precedent -- if your complaints are work-specific or are shared among other employees, the online comments are virtual "water cooler" chatter and are protected.

That's why, two years ago, a Chicago car salesman's firing was contested after he had complained on Facebook that the BMW dealership he worked at "served overcooked hot dogs, stale buns and other cheap food" at a sales event, according to The Associated Press. (His firing was ultimately upheld because, in addition to the hot dog comments, he also posted photos and made comments about an accident that happened at the dealership.)

The year before that, in what was reported to be the first major NLRB ruling regarding a Facebook posting, the labor board filed a complaint against a Connecticut ambulance service that had fired an emergency medical technician for "violating a policy that bars employees from depicting the company 'in any way' on Facebook or other social media sites."

"The takeaway, I think, is that the board has become more focused on, and aggressive about, section 7 of the National Labor Relations Act," the section that says employees not only have the right to bargain collectively, but also "engage in other concerted activities [for] mutual aid or protection," Ms. Danaher said.

Even so, the NLRB's stance on Facebook postings is not a get-out-of-jail-free pass.

"Employees should not take this as permission to write whatever they want on their Facebook pages," she said.