When does the layer of an organisation stop to be part of the organisation and become a separate entity?

Organisations operate in increasing complex environments that require sophisticated and sometime dedicated areas and means of interaction. You see an on-going specialisation enabled by lower costs of transactions and the appearing of specialised external partners and intermediaries.

Where does the exact border begin and stop, what is virtual, outsourced, controlled? In other words where does the layer become a separate entity?

How far can the effective influence of the design for a specific organisation stretch?