Thread:ChidoriSpark27/@comment-3030647-20150114235353/@comment-24071637-20150115073500

From what I could gather the Tenseigan wasn't created from the accumulated Byakugan anyway. Hamura sealed his own Tenseigan into an Energy Vessel, this very same vessel is the altar and what the Otsutsuki sealed their Byakugan into.(So both Tenseigan and Byakugan are in the Energy Vessel but still separate, I think) Doing this they could use the Energy Vessel as a source of energy, specifically senjutsu chakra. The Tenseigan is actually awakened like the Rinnegan, by combining the two bloodlines, I think it has to be a pure Byakugan that is involved as well. So undiluted blood, so it may be specific to the heir/heiress family line. After The Last Hanabi's Byakugan loose the Tenseigan, so no one knows where it. Now this could be wrong as I'm paraphrasing from FF-Suzaku's discussion on the mother site and even then he can't confirm it all.