While social media is a great tool for many things -- promoting your business, keeping up with friends and family members, uploading filtered pictures of your morning coffee -- it's also a fertile breeding ground for questionable, often ill-advised posts.

Case in point: Back in November 2011, Patrick Snay reached a discrimination settlement with Gulliver Preparatory School, where he used to be employed as headmaster. The terms were confidential, but that apparently didn't stop Snay from sharing them with his daughter. And that didn't stop her from posting them on her Facebook page.

“Mama and Papa Snay won the case against Gulliver,” Dana Snay posted to her 1,200 Facebook friends, the Miami Herald reported. “Gulliver is now officially paying for my vacation to Europe this summer. SUCK IT.”

Unsurprisingly the post was sniffed out by the school's attorneys, who notified Snay that the school would no longer be paying him anything, as the terms of the agreement had been violated.

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Last year, the Herald reported, Snay won a Circuit Court ruling to get his $80,000 back, but Judge Ann Wells overturned the ruling last week. “Snay violated the agreement by doing exactly what he had promised not to do,” she wrote. “His daughter then did precisely what the confidentiality agreement was designed to prevent.”

There's an important, if rather obvious, lesson to be gleaned from all of this: don't share confidential information with employees unless it's absolutely necessary. And make sure your company has a hard and fast policy regarding social media. Oversharing sensitive information may seem like an obvious no-no, but a single misguided post from one employee can land your entire business in hot water.

While some rules may seem like no-brainers, it's still important to have a policy in writing, and ensure that all employees are up to speed on what's acceptable and what's not. Be explicit. Because sometimes rules, however simple, need to be spelled out.

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