ISO2002MF 

Conformance and Interfaces (OO Concepts for Native COBOL)

The term "conformance" is used in this document with several different meanings. In the context of object orientation, the term "conformance" is used to describe a relationship between object interfaces, and it is the basis of such fundamental features as inheritance, interface definitions, and conformance checking.

Note: Conformance checking is done at compile time only, except when using an object modifier and when invoking a method using a universal object reference.