Under ‘I’, we covered elements of technical interoperability. R1.1 is about legal interoperability. What usage rights do you attach to your data? This should be described clearly. Ambiguity could severely limit the reuse of your data by organisations that struggle to comply with licensing restrictions. Clarity of licensing status will become more important with automated searches involving more licensing considerations. The conditions under which the data can be used should be clear to machines and humans.