Musk's social media antics were part of an April Fool's prank, but investors weren't laughing. Tesla shares dropped another 5 percent, according to The Washington Post, with business experts openly questioning Musk's ability to lead the multi-billion dollar company.

For every well-executed corporate hoax, there's an overeager company whose ill-conceived pranks have blown up in their faces, sometimes badly.

To ensure readers and prank subjects caught on, WWD printed “Happy April Fools’ Day” upside down at the end of the column. EXCLUSIVE: Former Flos B&B Italia Group CEO Daniel Lalonde Moves to Vita, a Division of Fiskars Group Looking Back at Mugler's Best Celebrity Fashion Moments Through the Years: Beyoncé,