Board Thread:Theories and Speculation/@comment-1512913-20150221101637/@comment-26302001-20150305233433

It doesn't say he lost it. It just has no mention, or illustration at all. Instead it pretty much says his strongest form is Sage Mode Kurama Form. Kabuto used Hashirama's DNA to rebuild Sasuke's heart. Seelentau confirmed that so he does have Hashirama's cells. Obito didn't use up all chakra fighting off black zetsu he passed out and was on deaths door.