Office pranks are all fun and games until someone loses a … lawsuit. Whether it’s a hit to a brand’s image, legal action by an unamused employee, or a breakdown in worker relations, an office prank that bombs can cost a company big. So before you start planning your big stunt, check out this list of office pranks that went horribly wrong.

1. Kick in the pants
The “Kick Me” sign may be a schoolyard classic, but the prank wasn’t appreciated by an employee at an Intel plant in 2012. After three swift kicks to the buttocks and many more laughs at his expense, Harvey Palacio filed suit against the company. In the interim, two employees were convicted of misdemeanor battery and fired by Intel.

2. Costly wordplay
Puns hurt. Just ask the Hooters in Panama City, Fl., where management was forced to buy a car for an employee in 2002 for misrepresenting first prize in an employee contest. After selling a record amount of beer, waitress Jodee Barry went to her bosses to claim the sales incentive she had been promised, “a Toyota”, and instead was awarded a “toy Yoda” doll. Amused, she was not. And neither was the restaurant franchise when they ended up having to pay up.

3. You have the right to remain mortified
Southwest Airlines customer service agent Marcie Fuerschbach was nearing the end of her probationary employment status with the airline when airport officers showed up at her kiosk claiming they had an outstanding warrant for her arrest. She was handcuffed and led outside in what was later revealed as a prank organized by co-workers. But when the cuffs came off, Fuerschbach sued for false imprisonment and intentional infliction of emotional distress. A Southwest spokesman said the airline was “shocked by her reaction” and was “just trying to make an employee feel welcomed.”

4. Wrong in the tooth
Assistants can be tempting targets for office pranks, but if you ever get the urge to surgically implant boar tusks in your subordinate while they’re unconscious, think twice. Specifically, think about Robert Woo, a Washington state oral surgeon who was forced to pay $250,000 after his assistant sued him for doing just that. (Shockingly, Woo got the last laugh when a state Supreme Court ruled that he deserved $750,000 because his insurance company refused to defend him against the charges.)

5. Thinking inside the box
Surprising someone at the office with a singing telegram? Embarrassing. Surprising someone at the office with your lifeless body? Traumatic. But that’s exactly what happened in 2012, when a man in Southern China sealed himself inside a cardboard box, forgot to poke air holes, and gradually passed out over the three hours it took for couriers to find his girlfriend’s office. He was eventually revived by paramedics, just narrowly avoiding a workplace fatality.

6. Dummy due dates
Glenn Howlett, a general manager with 30 years experience in London’s city hall, was on a well-deserved vacation when he received a phony memo from co-workers saying his big corporate renewal plan was due far sooner than expected. Howlett lawyered up and threatened to quit over the gag, which left city council with a black eye once the hoax made headlines.

7. Reckless amusement
If you’re ever tempted to give a rookie a good ribbing, try to leave masks, fake guns and firecrackers out of it. One firefighter lost his job and four others received demotions and suspensions after they tried to scare two new hires by staging a fake robbery at a Georgia firehouse in 2011. A video of the prank made its rounds on the web shortly after the incident, causing major headaches for city officials.