An assertion that is defined by the TM Application as being present in every topic map graph that conforms to that TM Application. TM Applications generally define built-in assertions for bootstrapping purposes and/or for allowing the topic maps that conform to them to incorporate the subjects defined in the TM Application definition, thus allowing such topic maps to be self-describing. The nodes that participate in built-in assertions have built-in property values that correspond to their arcs, and built-in values for their subject identity discrimination properties (SIDPs) such that the merging of the built-in assertions in conformance with the assertion merging rules specified in [parid0374] 5.2.8.2 will occur.

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