What does the "final published version" refer to in copyright? I'm trying to figure out if I can put a PDF that I give Springer on arXiv.
Note that this PDF has had further changes made to it after it has been already accepted by a conference; it's not the same as the conference submission.

Springer's copyright transfer form says:


  Prior versions of the Contribution published on non-commercial pre-print servers like ArXiv/CoRR and HAL can remain on these servers and/or can be updated with Author’s accepted version.
  The final published version (in pdf or html/xml format) cannot be used for this purpose.
  Acknowledgment needs to be given to the final publication and a link must be inserted to the published Contribution on Springer’s website, by inserting the DOI number of the article in the following sentence:
  "The final publication is available at Springer via http://dx.doi.org/[insert DOI]".


...but I can't tell what "the final published version" refers to.

Does it include the final PDF that I submit to them for publishing?
Or is it only the official PDF that they actually publish on their site?

(I presume the two could be different, since they could make their own edits?)

My guess is that it's only the latter, since they seem to imply the final version is the one with the DOI, but I'm not sure.
The usual workflow with Springer is:


You prepare your paper, and submit it as a PDF file to the conference.
The conference reviews the paper, and you get the acceptance notification + conference reviews back.
You revise your paper, and submit the source code to Springer.
Springer does copyediting, and you get the page proofs back.
You check the page proofs and submit your corrections to Springer.
Springer prepares the final PDF and posts it on their web page.


(Note that steps 1–3 involve work from you + research community. Steps 4–6 involve some added value from the publisher.)

The "author-created version" refers to your output after step 1 or 3. This is what you can self-archive.

The "final published version" refers to Springer's output after step 6. This is a version you cannot self-archive.

(IANAL, etc.)