Hi Heni This may be useful. Please don't take too much notice of the Mei.
Both Hirotsugu and later Hiromasa were active smiths in the mid-Muromachi period in Sagami province and they were followed by Tsunahiro and Fusamune. There were a number of generations of Hirotsugu, but this example is the generation active in the Tenbun era and it is believed that he left Kamakura after the downfall of his employer, the Miura clan. He then travelled around the Tokai-do districts engaging in sword making.This smith makes a uniquely shaped nakago in that the bottom of the Nakago is noticeably squeezed. In his early years he signed "Soshu ju Hirotsugu" but in his later years, simply "Hirotsugu" in two characters. As is seen in this Tanto, Shingane or core steel is often seen on the Tanto of Sue-Soshu smiths. Even so, the Hamon has many Hataraki (activities) and the good Horimono identifies the blade as a Sue-Soshu sword.