The seventh theory says that dotaku were disposed of (in a lump if many existed) in the ground because they were not necessary any more due to political social changes (Kageharu MISHINA, Yukio KOBAYASHI and others).
政治的な社会変動により、不要なものとして（多数の場合は一括して）埋納したという説（三品影映・小林行雄等）。