It seems very plausible that an engineer might be more productive at Company A rather than Company B. But that's less likely to be the case for some specific id

It seems very plausible that an engineer might be more productive at Company A rather than Company B. But that's less likely to be the case for some specific ideas in some documents; if Company A is better at using some ideas you'd think they'd generally be better at coming up with them in the first place. So in terms of the benefits to society it makes sense to facilitate engineers moving but not documents.