Here's a real and true story about how separate Microsoft teams communicate and coordinate:

Few weeks ago, some Microsoft team from the US deprecated some critical service used by other Microsoft products. They just shut it off without notifying anyone. Other teams from other Microsoft offices in the rest of the world found about this deprecation when their production builds started failing to log customers in to the applications that they need for their businesses. People were called in from their vacations, emergency meetings were held to play hot potato with responsibility. Clients were PISSED. I stopped following the drama before it was resolved.