The luckiest of rock stars fuel fan intrigue with their onstage antics, but too often the drama plays out in courts and legal documents. In an industry of inherently butting egos, there are bound to be some rocky relationships. That's when the justice system is called on to intervene and someone gets served. Here we take a look at some of rock 'n' roll's nastiest lawsuits.

The causes are many. How many of us still hang out with our childhood friends, let alone work with them? It's natural to grow apart after decades, but so many artists are tethered to the pals of their youth, after their teenage band hits it big and forces them to remain coworkers for decades. When the friction builds, so, too, do the legal bills.

That's not always the story. Some legal battles are a matter of artist vs. machine. When the band, previously focused exclusively on the music, suddenly realizes their manager or record label has gained the upper hand, they fight for the right to their intellectual property and finances. Or sometimes, a label will take action by claiming that the artist has not lived up to the terms of their contract. Then there are those moments where a copyright holder thinks somebody's song is a little too close to their own.

And here and there, we hear about a rocker's bonehead move, lashing out against — a fan, a bandmate, a manager — over who-knows-what. Take a spin through these lawsuits that time and again filled news articles and splashed across screens. Whose side are you on?