Couldn't, in theory, Microsoft acquire a newly formed subsidary that is US based that owns Activision and its properties, also legally moved to the US, there by circumventing this?
Basically, Activision would lease its UK IPs to the newly founded company, maintaining access (with extra steps I imagine, never the less), and Activision UK would technically be a separate entity
While true, sometimes these loopholes aren't super enforceable to stop without explicit legislation in the US (see things like Texas Two Step bankruptcies). I however do not know how it works in the UK
Basically, Activision would lease its UK IPs to the newly founded company, maintaining access (with extra steps I imagine, never the less), and Activision UK would technically be a separate entity