Earlier quoted context omitted.
> while still being officially allowed to take the devices home with us, use them privately and so on. Who owns the rights to IP developed on these company-owned laptops? One of the biggest problems with this kind of ‘unspoken flexibility’ is that any side projects you work on are in-part owned by the company, under most standard agreements.
Isn't that the case regardless of what laptop you're using? As far as I can tell you should assume any side projects are Copyright (c) your employer unless you talk to legal first and make an arrangement (for each project). See for example: https://www.joelonsoftware.com/2016/12/09/developers-side-pr...
Legal precedence around IP ownership - when you've used company-owned machines - is far less clear.