Scrum artifacts or process documents provide guidance or links in the process framework.

4.1 Product Backlog

The Product Backlog is the core artifact of Scrum. In larger organizations management of the Product Backlog is unnecessarily complicated. What are the key messages, what are the rules for a Product Backlog, which also apply in scaled environments?

First of all, there is only one product backlog. For this there is a very clear statement in the Scrum Guide:  

The Product Backlog lists all features, functions, requirements, enhancements, and fixes that constitute the changes to be made to the product in future releases. […,] Multiple Scrum Teams often work together on the same product. One Product Backlog is used to describe the upcoming work on the product. A Product Backlog attribute that groups items may then be employed.