Id Assertion MUST be able to consume any valid Document. MAY consume Well-formed instance documents which do not satisfy local-schema validity against the originating Document. MUST be able to consume any Well-formed Document which satisfies local-schema validity against the originating Document exposing all of the element node and attribute node content in the data model. MUST produce a data model exposing all of the element node and attribute node content described by the originating Document. MAY allow the production of Well-formed instance documents containing values exposed in the data model which do not satisfy local-schema validity against the originating Document. MUST be able to produce Well-formed instance documents which satisfy local-schema validity against the originating Document containing values exposed in the data model. MUST be able to process any Document conforming to this specification