The word canon has been argued about across all anime fandoms. A lot of the popular animes made movies that could fit into the main timeline, but the mangka's won't incorporate what happens in the movies into the main story. The best way I tend to look at Inuyasha's movie series are like side quests, doesn't impact your underst

I apologize if I am misunderstanding what you are saying. If you asking if Rumiko Takahashi made the storyline of the movies, she only supervised the script. She makes sure that the characters she created aren't being misused.

I was saying that at least Movie 3 is "canon" in terms of what we have seen in Yashahime. I don't know about the other movies since it's been a while since I've seen them.