A proposal has been made for a fast-track amendment to IEC 62366 related to use with legacy products. Application of “62366 Medical devices – Application of usability engineering to medical devices” to legacy devices has been inconsistent and problematic; this proposal is for a fast track amendment to address what is called User Interface of Unknown Provenance (UOUP). This proposal includes a draft for a section to address this, including review of field history and a simplified approach for addressing usability in terms of identification of frequently used and primary operating functions and a risk management review.