The present invention relates to an information recording apparatus, an
information recording method, an information recording medium, an
information reproducing apparatus and an information reproducing method
by which in the case in which the present invention is applied to an
optical disk system by, for example, a compact disk or the like and data
or the like related to copyright is recorded by partial change of a pit
shape or the like, the data can be reproduced with certainty without
repeatedly recording the data. According to the present invention, with
regard to a defect having a size by which at least main data can be
reproduced correctly, 1 bit of sub-data SB is allocated to a pit row or
the like having a predetermined length or more such that the sub-data SB
can be reproduced correctly.