FDA's investigational device exemption (IDE) regulation is found at 21 CFR part 812. Under 21 CFR 812.5, investigational devices must bear a label that states the following:
"CAUTION -- Investigational device. Limited by Federal (or United States) law to investigational use."
The labeling may not represent that the device is safe or effective for the purposes that it is being investigated for (21 CFR 812.5(b)).