Sealing Designation

封印指定 - fuuin shitei

A Sealing Designation is a title 'of greatest honor' bestowed upon a prominent magus; an edict handed down by the Mage's Association to maintain and protect special thaumaturgical abilities which cannot be acquired through study.

The Sealing Designated is deemed "precious" and the Association will mobilize the greatest effort to secure their flesh and blood, their body's potential. In other words, the magus is incarcerated, becoming a sample preserved at its present condition and level of ability.

To those magus Designated, it is an outrage - not because it is the equivalent of a death sentence, but because of who they are; as they are all prominent magi, they would have spent all their lives devoted to their research, and reject a situation where they will lost their life's work.

Once Designated, there are usually two paths a magus can choose: becoming a Hermit, or a Philosopher.

Hermit
隠者 - inja

Degraded magi who have completely secluded themselves from the outside world, transmitting their knowledge only to their successor. Although the Association shows interest in acquiring the fruits of their research and keeps them under surveillance, since Hermits are not an immediate threat they are usually left alone. The situation might be different if the Hermit has a truly extraordinary work.

Philosopher
賢者 - kenja

Great magi who strive to reach new heights. A menace that, after receiving their Sealing Designations, abandoned all codes of conduct for the sake of continuing with their research without being bothered. Since they act without restrain, they are capable of obtaining great results in short amounts of time, but as a consequence victimize a great number of unrelated people. Note that the standards of the Association are based not on morality, but on the principle of the preservation of Magecraft. Regardless of what crimes a magus may perform, as long as he does not threatens the secrecy of Thaumatugy he will not be targeted.

Enforcer
実行者 - jikkousha

The agents that hunt down the magi that receive Sealing Designations, they are the equivalent to the Mage’s Association what the Executors are for the Sacred Church. Though their targets are the same, Enforcers and Executors rarely work together since the formers look out to retrieve the work of the magus, while the latter usually have orders of destroying all evidences on the spot. Looked down by the upper ranks of the Association, although they are supposed to suppress anything that might reveal the existence of Magecraft to the general public, great events and rituals such as the Heaven’s Feel are outside their scope of work. Bazett’s participation on the 5th Grail War as a representative of the Association was due to Kotomine’s recommendation.

Source

 * Jonnobi.
 * The Tsukihime Lab.
 * Fate/hollow ataraxia, "Forest" scene.