I would propose the following wording, or some variation there-of:
This question appears to be off-topic because it is about licensing. Questions on licensing should be referred to the vendor, and an answer obtained in writing from them.
Some sample questions that I've voted-to-close with this reason:
How to verify an oracle database license
Also, this proposed question contained within this meta-question about licensing being on-topic: Can I ask a question about ODBC driver and license?