Global geographic spread of the companies is the standard reality as much as the Innovation is. Traditionally companies tend to have their Innovation teams co-located in one location even when teams are from different backgrounds. In the Strategy & Business Article Overcoming the Global Trade off authors discuss how to not only manage innovations in teams spread across locations but also leverage the same for Innovation projects.
They propose three things to ensure that teams across locations can innovate together. I like their first suggestion of limiting the number of locations across which your teams are located. This means while it is more than one location, it need not be every location. You carefully choose the functions / skills / knowledge base required and choose people in those locations. The second suggestion that technology should be leveraged by the teams to create a culture of co-location. This, I think is a default need for organizations that are dispersed across location, irrespective of the kind of work to be done, and most organizations have the infrastructure in place for this. Their third point says that dispersed teams need more project management and senior management bandwidth, something I think is again applicable to all functions that are performed by global teams. Yes,, when you involve external entities be it people or organizations, that is when you need to have very well defined problem, systems, processes and infrastructure to handle the new flow of ideas.