Shares of Berlin's ReWalk Robotics Technologies fell 13% on news of an FDA warning letter. The document was actually sent to the company in September (when it went by the name Argo Medical), but only just disclosed by the FDA, perhaps in a bid to raise the stakes. The FDA said that the maker of the ReWalk wearable exoskeleton, which provides mobility to those with a spinal cord injury, has repeatedly blown off the FDA's requests for a postmarket study plan. The agency said it issued an order for a postmarket study upon de novo approval in 2014 because "the device's failure to prevent a fall would be reasonably likely to cause serious user injury and/or death through fall related sequelae, such as traumatic brain injury (TBI), spinal cord injury (SCI), and fractures to the user." The letter lists several instances of Argo's failure to comply with the order, and accused the firm of selling a misbranded device under section 522 of the Federal Food, Drug and Cosmetic Act. The FDA once again asked for the study plan in the warning letter. Here's the letter | More