Board Thread:Theories and Speculation/@comment-1512913-20150221101637/@comment-6769189-20150222114559

Hamura was the first to unlock it. It's an extension of the Byakugan. Created from mixing Otsutsuki and Hyuuga. I believe the databook says its equivalent of the Rinnegan.

Kaguya more than likely had the potential but Rinne Sharingan got the job done.

Imagine, in some alternate universe, Kishimoto made the story so that Kagya had the Tensei Byakugan with Sharingan eyes and the tragic asshole rival of Naruto was Neji. Sasuke died in the war. Hinata killed all the other Hyuuga. To save the village. Kakshi has 1 Byakugan. The other belonged to Obito Hyuuga......