Further, Nika Sojo are regarded as fake documents since there are no records in ancient times, but according to Fuji Taiseki-ji Temple, there is a document by Niccho, who was one of roku roso (the Six Senior Disciples of Nichiren), called Honzon Sho Tokui Sho Soegaki (The Covering Letter of "Kanjin Honzon Sho" (the Spiritual Contemplation and the Most Venerable One)), written in the twenty-seventh year after Nichiren's death.
さらに二箇相承は、上代には記録が無いため偽書であるとされているが、富士大石寺によると日蓮滅後27年目に六老僧の一人日頂の本尊抄得意抄添書があるとされる。