ISO2002MF 

Interface Inheritance (OO Concepts for Native COBOL)

Interface inheritance is a mechanism for using one or more interface definitions as the basis for another interface. The inheriting interface has all the method specifications defined for the inherited interface definition or definitions, including any method specifications that the inherited definition or definitions inherited. The inheriting interface may define new methods augmenting the set of inherited method specifications. The inheriting interface must always conform to each of the inherited interfaces.