Emperors themselves were deeply involved with the collection of the precious books and production of copies, and many of the contents and titles were written by the Shinpitsu (emperor's own handwriting), as for book collection seals, the era names on the throne such as the Emperor Gosai ('Meireki era'), the Emperor Higashiyama ('Genroku era'), the Emperor Gosakuramachi ('Meiwa Era') and so on were used, or unified seal called 'imperial line bunko' was used (for example, the Gosai Emperor, the Sakuramachi Emperor and the Emperor Komei), and some emperors made unique book collection seals such as 'Osahito,' 'Konohana,' 'Tenen' and so on, like the Emperor Komei.
貴重書収集・副本作成の作業には天皇自身も深く関与し、その宸筆によって本文・外題が記されたものが多く、蔵書印も後西天皇（「明暦」）・東山天皇（「元禄」）・桜町天皇（「延享」）・後桜町天皇（「明和」）など在位中の元号を用いたものや「皇統文庫」という統一印を用いる例（後西・桜町・孝明天皇）などが使用され、孝明天皇のように「統仁」・「此華」・「天淵」などの独自の蔵書印を作成する天皇もいた。