In LARGE Scrum environments, additional artefacts are necessary to ensure transparency throughout the whole organisation:

Company Product Backlog

All Customers communicate their ideas and Stories to the Company Product Owner. Out of these Stories, she then creates and prioritises the Company Product Backlog, from which the Teams can start pulling the top priority Items.

Just like a Scrum Team needs a Product Backlog and a Taskboard, a scaled Scrum Team requires a Company Product Backlog and a Company ScrumBoard. In most cases, this does not yet refer to the whole company, but rather a department or at least more than 2 Teams.