OICA perspectives for addressing cases of technologies voluntarily installed on vehicles by manufacturers that subsequently become subject to mandatory installation. In particular, the presentation addresses cases where a UN Regulation addresses technologies that are optional in some markets, but mandatory in others. For example, UN R116 includes both vehicle alarms and vehicle immobilizers. Alarms are presently optional across parties to the 1958 Agreement, but some parties require immobilizers. This divergence creates confusion over the validity of UN R116 approvals across all parties to the Agreement.