Of course, gag orders (and PR common sense), prevent them from giving you this information.
But given what we know about the NSA and the context around it, I'm enclined to trust The Guardian and Snowden about it.
> This also seems inaccurate. Apple has never claimed you need to buy a new phone if the home button breaks. The actual issue is that the home button is part of the security system of the phone, runs its own fingerprint detection and is paired with the mainboard, and thus cannot be replaced without updating this pairing, otherwise there would be a trivial security break for the fingerprint protection. As a result, only Apple have the required access to replace the button, and thus third-party replacements are impossible.
No, the failure I'm refering to is of the iPhone 4 home button, which didn't have a fingerprint sensor yet.