https://www.cnbc.com/2018/10/08/apple-tells-congress-it-found-no-signs-of-a-hacking-attack.html

Apple's top security officer told Congress on Sunday that it had found no sign of suspicious transmissions or other evidence that it had been penetrated in a sophisticated attack on its supply chain.

Apple Vice President for Information Security George Stathakopoulos wrote in a letter to the Senate and House commerce committees that the company had repeatedly investigated and found no evidence for the main points in a Bloomberg Businessweek article published on Thursday, including that chips inside servers sold to Apple by Super Micro Computer allowed for backdoor transmissions to China.