<rdf:RDF

xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"

xmlns:owl="http://www.w3.org/2002/07/owl#"

xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#">

<owl:Ontology />

<owl:Class rdf:about="http://owl2.test/rules#C_Sub">

<rdfs:subClassOf>

<owl:Class>

<owl:unionOf rdf:parseType="Collection">

<owl:Class rdf:about="http://owl2.test/rules#C1"/>

<owl:Class rdf:about="http://owl2.test/rules#C2"/>

</owl:unionOf>

</owl:Class>

</rdfs:subClassOf>

</owl:Class>

</rdf:RDF>