Note that there is a point where we check whether ClassA is assignable to MasterDbo<D>. We use JLS assignability for this check. If we instead at that point used CDI assignability rules (not JLS assignability rules) the check would pass. It is not very clear which rules to use when. The only indication is the use of phrase "according to these rules" which is used e.g. in the first bullet point in 5.2.4. I understand it that the lack of the phrase indicates, that the JLS rules should be used but this may need clarification of spec.