Hyūga Main Family's Juinjutsu

This seal is given to all branch house members in the Hyuga clan by members of the main house. Its main purpose is to seal their Byakugan ability should they die, preventing an enemy from learning its secrets. Its secondary purpose is to control the branch house, since it can be activated at will by a main house member with a hand seal that only they know about, to destroy the wearer's brain cells.

The seal is placed on the wearer's forehead when the next member of the main house turns three years old, (Neji Hyuga received his at the age of four on Hinata's third birthday), and is only removed upon their death.

In the original manga and Viz's volume distribution of the manga, the seal is shown as a manji similar to a swastika, the sauwastika. In the anime and Viz's monthly distribution of the manga, it was changed to a simple saltire for fears of negative reactions, as the opposite-facing swastika was adopted as the symbol of the Nazi party.