https://www.theregister.co.uk/2019/10/04/oracle_virtualbox_merula/

Merula Limited, a UK-based network service provider, recently received a bill from Oracle for $12,200 for using the company's proprietary VirtualBox Extension Pack, which provides extra capabilities for the free GPL-licensed VirtualBox hypervisor.

For Richard Palmer, director of the company, this was a perplexing demand. As he explained to The Register, "Merula does not operate or manage any computer using VirtualBox or any Oracle software."