Government Backdoor – The Clipper Chip – flawed
The final nail in the coffin came after Matthew Blaze, then a 32-year-old computer scientist at AT&T Bell Laboratories, discovered a flaw in the Clipper system that would have allowed anyone with technical know-how to get access to the key to encrypted communications.
.. Leading technology companies, including Microsoft, Facebook and Twitter, have been moving to transient messaging plans that dispose of the encryption key to customers’ messages once their session ends.