SuperMicro response:
https://www.supermicro.com/newsroom/pressreleases/2018/press181004_Bloomberg.cfm
Apple response:
https://www.apple.com/newsroom/2018/10/what-businessweek-got-wrong-about-apple/
Amazon.com response:
https://aws.amazon.com/blogs/security/setting-the-record-straight-on-bloomberg-businessweeks-erroneous-article/
More info:
https://www.lightbluetouchpaper.org/2018/10/05/making-sense-of-the-supermicro-motherboard-attack/
https://blog.senr.io/blog/impervious-implants-splintery-supply-chains
https://motherboard.vice.com/en_us/article/gye8w4/chinese-supply-chain-hack-apple-bloomberg