Related to the business
The wording I've seen in various contracts around this often includes something like "...related to the business of the company, *or capable of being used by*".
That 'or capable of being used by' can essentially include whatever they might choose it to mean: "Sure we're a travel agency today, but we could start selling software tomorrow if we decided we owned some."
I've always recommended to any devs I've managed that if they're working on something in their own time, they let us know about it so we can get the MD to give them an opt-out in writing saying the company's aware of it, and don't consider it their IP.
Wouldn't apply in this case, obviously!
Biting the hand that feeds IT
