I'm not familiar with things like that, but there might be certain countries where you have policies like that. As far as Canada is concerned, we might be more laissez-faire because Bombardier has been doing rather well so they might be sort of left to do their own things.
Pratt & Whitney Canada might be in a similar situation. They have a lot of work to produce here, but engines might be a tad different because the components are a lot smaller and they tend to do everything in-house. Pratt & Whitney Canada is a subsidiary of a U.S. company so they don't do all the work. They do a certain part of the work, like the smaller engines.
So division of labour in the aerospace industry does exist.