BIPA "does not contain" a definition of what it means to suffer injuries, the court said, and in "popularly understood" terms, you've faced those damages simply through the violation of the law. The court added that the whole point of the law was to give users greater control over when and how companies collect biometric data. If firms can escape liability so long as they don't cause tangible harm, your right to control your privacy "vanishes into thin air."

The state's Chamber of Commerce objected to the ruling, claiming that it would "open the floodgates" to lawsuits that would hurt the Illinois economy.

That's not necessarily the case. Still, there's little doubt the decision will have significant ramifications. Google, Facebook and others have faced lawsuits accusing them of violating BIPA by tagging faces in photos without asking users. Google recently had a Photos-related case tossed out because the plaintiffs couldn't show that they'd faced "concrete injuries," but that argument might not hold up after the Six Flags ruling.