Is it possible to pull the auto (non-user) generated video transcripts from any of the YouTube APIs?
You may refer with this thread: How to get "transcript" in youtube-api v3
If you're authenticating with oAuth2, you could do a quick call to this feed:
http://gdata.youtube.com/feeds/api/videos/[VIDEOID]/captiondata/[CAPTIONTRACKID]
to get the data you want. To retrieve a list of possible caption track IDs with v2 of the API, you access this feed:
https://gdata.youtube.com/feeds/api/videos/[VIDEOID]/captions
That feed request also accepts some optional parameters, including language, max-results, etc. For more details, along with a sample that shows the returned format of the caption track list, see the documentation at https://developers.google.com/youtube/2.0/developers_guide_protocol_captions#Retrieve_Caption_Set
Also, here are some references which migh help: