The reality was more likely that these family names were not permitted to be written in public documents, such as Shumon Ninbetsu Cho (religious and population investigation registers), and in some cases, these names remain as epitaphs on tombstones or family registers of deaths, both of which were provided strongly with characteristics of private documents.
宗門人別帳などの公文書への記載が許されなかったというのが実態に近く、私的な文書の色彩が強い墓碑銘や過去帳に遺されているケースもある。