A method and apparatus for creating a machine-readable medium such as a CD
or a DVD disc is disclosed. The disc includes encoded copy protection data
that, when decoded and re-encoded, produces a tracking prevention sequence
of bits that causes a duplicate disc (containing the re-encoded copy
protection data) to temporarily lose tracking. The temporary loss of
tracking is utilized to render the duplicated disc unusable by placing key
data immediately following the encoded copy protection data.
