What about if the Head Office is the one doing all the procurement and the branch office located in another country is just doing the selling, does that mean the branch office is excluded from the Purchasing requirements of ISO 9001 2015?
It all depends how you established your QMS. If you defined that the purchasing process is centralized and the purchase is conducted from one place for entire company than the branch office doesn't have to fulfill requirements for purchasing because all they do is an internal purchase and you don't have to establish the entire process.
If you have separate QMS for the branch office than you need to define the purchasing process inside the branch.
Thank you so much for the clarification, that helps. Yes, the branch office actually has its own QMS so we will just define its own internal purchasing process but only for their office supplies because all the products they sell are coming from head office.