Public Key Fingerprint (SHA1) valid Until GTS Root R1 RSA 4096, SHA-384 e1:c9:50:e6:ef:22:f8:4c:56:45:72:8b:92:20:60:d7:d5:a7:a3:e8. If you are building products that intend to connect to Google property moving forward you need to at minimum include the above Root Certificates.”]
Source: https://security.googleblog.com/2017/01/the-foundation-of-more-secure-web.html