it’s a supposedly a very very famous blade, 村雨Murasame by 津田越前守助広Tsuda Echizen no Kami Sukehiro, also known as 村雨助弘Murasame Sukehiro, rated as 特別重要刀剣Tokubetsu Juyo Token.
You should be able to find more info from here.
According to hearsay this blade is currently in hand of a Chinese collector

muramse