Historical Rules · 23 April 2010
Rule 806.7e
Official source text from the 23 April 2010 Rules release
If a team has priority and neither player on that team wishes to do anything, that team passes. If both teams pass in succession (that is, if both teams pass without any player taking any actions in between passing), the top object on the stack resolves, then the active team receives priority. If the stack is empty when both teams pass in succession, the phase or step ends and the next one begins.