Katsushika KUSAKABE wrote "Yakushiji Satsumei Shaku (Interpretation of Inscription of Yakushiji Temple)" in 1794 and pointed out the existence of the inscription "the eighth year of enthronement, Boshin" on the East Pagoda of Yakushiji Temple, noted that the tai sui article of the history of Tenmu was in the second year instead of the first year, and asserted that if the Jinshin year was not an interregnum, Otomo had the Imperial Throne.
寛政6年（1794年）には、日下部勝皋が『薬師寺檫銘釈』を著して、薬師寺東塔の銘文「即位八年庚辰」の存在を指摘し、天武紀の太歳記事が元年ではなく2年にあることに注意を喚起して、壬申年は空位でないなら大友が皇位にあったのだと主張した。