This paper deals with the problem, coming from an industrial context, of ontology transformations. EADS, as a major aircraft manufacturer faces the problem of integrating works of experts from different domains using different notations. Addressing this Domain-Specific Language (DSL) problem, we previously developed a solution based on OWL2 ontologies for the integration of multiple domains at the abstract syntax level. Our next step is then the production of visual concrete syntaxes from this abstract syntax, for each domain. Considering this problem as a transformation issue, we raise the challenge of ontology transformations. We provide an OWL2-based rule language for the expression of such transformations. Validating this approach, our rule language has been implemented in a rule and transformation engine and tested on applications coming from the industry.