A recording medium and a recording apparatus store manufacturer
information to support specific functions for each manufacturer and a
method therefore. A reproducing apparatus reproduces the manufacturer
information to support specific functions. When the recording apparatus
modifies the contents of the recording medium, the manufacturer's
identification code is recorded. The recording apparatus and the
reproducing apparatus checks the identification code on the recording
medium before using its own manufacture information item for some
specific function. Also, a time required to determine whether the
manufacturer information items are effective is reduced.