Thread:Shabook/@comment-26917787-20160418213944/@comment-112155-20160418214429

That list as of now, is meant for things seen onscreen. Maria Stark was portrayed in the Iron Man 2: Public Identity comic, written by Justin Theroux (the screenwriter for Iron Man 2), but it was kept under the "Mentioned only" section until Captain America: Civil War actually cast an actress for her.

Same with the Mandarin, he is mentioned only despite he first appeared in the Iron Man 3 Prelude.