Copy Control Information (CCI) is a two byte flag included in digital television streams that allows content owners and cable operators to specify how content can be duplicated.
Originally defined as part of the 5C copy protection specification devised by DTCP working group back in 1998, it was later defined as part of the FCCs Plug and Play agreement in 2003.
DVR platforms such as TiVo and Windows Media Center are responsible for reading the flag, decrypting the stream if necessary and storing the content in a way that enforces the flag set.
The application of the CCI flag was specified on page 30 of the FCC Plug and Play agreement.
Some operators tend to set all programs as Copy Once, preventing further distribution after a single PVR recording, and others tend to set all programs as Copy Freely.