The Tosefta was redacted around 400 A.D. (we have no exact knowledge). The document encompassed three types of teachings. First, it contained direct citations of statements in the Mishnah, which were then glossed or expanded. Second, it included statements that related to, but did not cite verbatim, statements in the Mishnah. These versions of rules cannot be fully understood without referring to their counterparts in the Mishnah. Finally, it presented statements that are entirely autonomous, in theme or in principle or in detail, of anything in the Mishnah. The first two types of materials depend upon, therefore are later than, the Mishnah itself. The third type can derive from the same period as the Mishnah. That type is quite small in proportion to the whole, certainly not more than 20 percent overall.