The MDR sets out some special rules on UDI for certain categories of devices:

• Custom-made devices: No UDI code is required on the label, but they must still be registered in EUDAMED.  The relevant UDI information must be included in the technical documentation.
• Implantable devices: the UDI-DI must be indicated not only on the packaging label, but also on the implant card that is given to the patient. This is to ensure effective traceability even after implantation.
• Reusable devices: in this case, a permanent marking of the UDI code (Direct Part Marking – DPM) on the device itself, if technically possible. The marking must be legible throughout the expected life of the device and must withstand cleaning, disinfection and/or sterilisation cycles.