It is clear that the chapters were not written by Murasaki Shikibu (though nobody can tell if it is a forged book or not), so it is often treated equivalent to forgery, and taken up for the study of forged books.
紫式部が書いたものでないことは明らかなため偽書・偽作とは言えないが、それに近い存在として偽書・偽作研究で取り上げられることは多い。