"We saw downloads for virtual box from your IP address but no licenses for your organization. Please let us know when is a suitable time to meet to explain the benefits of being licensed correctly."
From the point of view of ISPs receiving such threats it is the most preposterous thing ever.
The company will then want to meet and discuss licensing, and if that doesn't happen they'll cut your IP addresses off.
This is typically something that's free for personal use but requires a license for commercial use. We've ran into this with a few things.
If any dev downloads and installs it within your org expect an email from them to check up on your licensing.
Now, perhaps this is what it takes to put paid to IPV4...