AACS LA stands for the Advanced Access Content System (AACS) Licensing Authority. Its founders include Intel, Microsoft, Panasonic, IBM, Sony, Toshiba, Warner Brother and The Walt Disney Company. The AACS LA controls the licensing of AACS. When a manufacturer created a Blu-ray or an HD DVD player, it must support AACS in order to play back content on the format. Licensing fees would be paid to AACS LA to incorporate the technology into the hardware.
If hardware is hacked and keys are stolen by a hacker, AACS LA can choose to revoke the keys and the license.
In the news:
AACS LA confirms AACS bypass (Jan 26, 2007)
AACS hacked again (Apr 10, 2007)
AACS cracked once again (18 May 2007)
New AnyDVD HD release from SlySoft targets BD+ (19 March 2008)