Rule 491.8.c

Control is not shared.

• 491.8.c.1 Players may not Hide cards at Battlefields controlled by their Teammate.
• 491.8.c.2 Players may not issue Standard Movement to their Teammate's Units.

Rulings that cite this rule

• What about “your units?” Is that shared between teammates too?
• Can my ally and I share control of battlefields?

Official Core Rules