Nobody

Frankly, I do not know how to explain more than my previous comments. I said that the first day of Koka era is Koka 1st year, 12th month, 2nd day. So naturally, Koka 1st year started on the 2nd day of 12th month and ended on the last day of 12th month. The following day is Koka 2nd year, 1st month, 1st day. How can Koka 1st year, 2nd month exist?

Frankly, I do not understand why you think that 2nd month of Koka 1 is a valid date after reading my comment.

I do not understand what you are saying. But anyway, the first day of Koka era was Koka 1st year, 12th month, 2nd day (Lunar calendar in Japan at that time). The day is equivalent to January 9, 1845 (Gregorian calendar), or December 28, 1844 (Julian calendar).

Maybe, 若芝 - Jakushi 平三郎 - Heizaburo

I do not think that the registration paper belongs to your blade. - The length of the blade written on the paper is 1-shaku 6-sun 4-bu (= 49.7 cm), whereas the length of your blade is 48.2 cm. - The pater says that there is a 清綱 mei on the omote-side, whereas there are three characters on the ura-side on your blade. Although I cannot decipher the three characters on your blade except the first 清, the inscription does not look like Kiyotsuna (清綱) to me. BTW, the registration paper was issued on July 10, 1951 (昭和廿六年七月拾日).

I think the mei is suspicious. The date on the nakago is 弘化元年二月日 (Koka 1st year, 2nd month). However, Koka era started from 12th month, and “Koka 1st year 2nd month” did not exist. The attached image shows Sukenaga’s genuine mei at around the same time (Koka 4th year, 2nd month). Ref. 刀　横山加賀介藤原朝臣祐永 (KA-070515)｜刀・日本刀の販売なら日本刀専門店の【銀座 誠友堂】

武器袖鏡 第二編 – Weapon Description Book Vol. 2 寶亀年間辛樻 – A chest in Hoki period (770-781) (91cm x 67cm x 45cm) 大和國法隆寺藏 – Owned by Horyuji in Yamato province

(所有)者住所 氏名 見積額 – Owner’s address, name, estimated value 田川郡糸田町上糸田 – Tagawa-gun, Itoda-machi, Kamiitoda 香月近芫 – Kazuki/Kozuki … 五〇〇円 - 500 Yen I guess red characters.

It looks like 豊成 - Toyonari (reading?)

More precisely for the place name, 下水内郡常盤村小沼 – Shimominochi-gun, Tokiwa-mura, Onuma Ref. Shimominochi District, Nagano - Wikipedia

The blade length written on the paper is 二尺四寸六分半 (2-shaku, 4-sun, 6-bu and a half = 74.7 cm). The length is longer than the standard length of katana in Edo period, even after its suriage. I can imagine that the blade was quite long for one of later users who made it shortened.

I am not sure about the correct reading for 橘窓子. However, I think that it might be possible to read Kissoshi (a euphonic change form Kitsusoshi). There is a word 橘窓 (kisso), which means a window with a view of citrus trees.

Yoshida Masaya (吉田正也) ?

Seems to be a family name.

髙尾 – Takao

A dealer suggested me plastic wrap for a short time.

FYI: Kago-yari (籠槍) Kago Yari : Minamoto Tadayuki. | Japanese Sword Online Museum

Only a guess work for No. 2 2. 白井紀代英 - Shirai Kiyoe/Kiyohide

I could read the 4th name. 川本武志 - Kawamoto Takeshi

宮城典真作 - Miyagi Norizane made. He was born in 1960, and he is still active.

1. 渡部盛継 – Watanabe Moritsugu 2. 白井□笑 – Shirai … 3. 山崎昭 – Yamazaki Akira 4. 川本□志 – Kawamoto … 5. 江口綜瞋 – Eguchi Soshin 6. 吉川皎園 – Yoshikawa Koen

－　濃州関住一文字源天秀鍛之 Noushu Sekiju Ichimonji Minamoto Amahide　－　日本刀の通信販売　明倫産業株式会社

There is at least one example, which shows the bottom of 繁 is not just three strokes.

奥州住兼定 - Oshu ju Kanesada Most likely gimei.

Address and name on the tag, 愛知縣中島郡稲澤町大字下津字東下町七十一番地 – Aichi-ken, Nakajima-gun, Inazawa-cho, Oaza-Orizu, Aza-Higashishimo-cho 71 伊藤徳兵衛 – Ito Tokube’e 日本刀（古刀） - Nihonto (koto)