Shihō
Shihō (嗣法) refers to a series of ceremonies in Sōtō Zen Buddhism wherein a unsui receives Dharma transmission, becoming part of the dharma lineage of his or her teacher.
Ceremony
Shiho is done "one-to-one in the abbot's quarters (hojo)".
Shiho, or denpo, is the Dharma transmission ceremony where the student inherits the Dharma, and is empowered to transmit the lineage. In the denpo ceremony, the student becomes an ancestor of the tradition and receives a robe and bowl, among other objects.
During the denpo ceremony the student receives a Shoshike certificate, which grants the power to perform Jukai, and the documents known as the "three regalia of transmission":
b) Daiji (the great matter, a cryptic symbolization of the content of the teaching. Again, there is a small extra sheet of paper that explains about the meaning of the symbols.)
c) Kechimyaku (the blood lineage, looks quite similar to the blood line transmission that you already wrote at the time of ordination)
d) Actually, in the lineage of Sawaki Roshi (and maybe other lineages as well) a student is told to write a fourth document on an extra sheet of paper, which is called Hisho (the secret document, which is encoded, but the code for deciphering is on the same paper, so once you hold it in your hands it is not so "secret" anymore.)