Board Thread:Naruto Discussions/@comment-25847976-20141218061108/@comment-1018594-20141218070131

...What?

I don't know where the idea of it being a main family jutsu came from, but the manga states that Hinata created the technique herself. Also, episode 390 was filler. You can't count filler as a valid citation for things like this.

Just because Hinata is no longer the heiress to the Hyuga Clan doesn't mean she's a branch member. That's decided at birth and can't be changed. She was able to marry Naruto because...they love each other, maybe? As far as we know, there's no laws or restrictions on who can marry who in Naruto.