The Outer-most region (OCT) typically refers to the outermost regions of the European Union (EU).

In Beneficiary projects, when adding mobility activities, if a Sending country has an outer-most region (Denmark, France, Spain, Portugal and the Netherlands), the Outer-most region flag can be checked to indicate if the mobility activity participant is coming from an outer-most region (OCT). 

Example of Outer-most region flag in a mobility activity in a KA131 Higher education project