Something I've noticed about Minato and FTG....I think

[Chatte]

Seals are made to stay not to dissapear as we've seen. You can break them by only releasing it how Orochimaru and later Jiraya did on Naruto, who later did it by himself when he wanted to take on Kurama's powers. So they don't dissapear.

However, as I stated, if the kunais are broken or the paper which has the mark I am sure that it would come as a problem for Minato.

 

[Lightbringer]

Seals are made to stay not to dissapear as we've seen. You can break them by only releasing it how Orochimaru and later Jiraya did on Naruto, who later did it by himself when he wanted to take on Kurama's powers. So they don't dissapear.

However, as I stated, if the kunais are broken or the paper which has the mark I am sure that it would come as a problem for Minato.

yeah but that was a different seal

 

[Chatte]

yeah but that was a different seal

We have seen different seals already. Naruto's seal, Sasuke's seal, Minato's seal. They weren't simply breakable. They needed a particular jutsu to be broken, otherwise they were staying untouched.

 

[Itachi Edo]

Regardless that is still one of the best justsu in the series.