In 2v2, can an opponent use Charm to move an ally's unit to my battlefield?

Ruling: The intent is that an ally cannot have their units at your battlefield, so an opponent cannot play Charm targeting an ally's unit and choose your battlefield. However, this rule is not currently in the Comprehensive Rules, making it a known issue.

Nuances:

• This is a known gap between intended gameplay and current rules text
• Charm cannot target friendly units, but can target an ally's units (which are not friendly to the opponent)