Ign:1 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:2 http://dl.google.com/linux/chrome/deb stable Release
Hit:3 http://us.archive.ubuntu.com/ubuntu zesty InRelease
Get:5 http://us.archive.ubuntu.com/ubuntu zesty-updates InRelease [89.2 kB]
Get:6 http://security.ubuntu.com/ubuntu zesty-security InRelease [89.2 kB]
Ign:7 http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04  InRelease
Hit:8 http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04  Release
Get:9 http://us.archive.ubuntu.com/ubuntu zesty-backports InRelease [89.2 kB]
Err:10 http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04  Release.gpg
  The following signatures were invalid: EXPKEYSIG 5A7D1D38BEB6D886 home:Horst3180 OBS Project <home:Horst3180@build.opensuse.org>
Fetched 268 kB in 0s (280 kB/s)
Reading package lists... Done
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04  Release: The following signatures were invalid: EXPKEYSIG 5A7D1D38BEB6D886 home:Horst3180 OBS Project <home:Horst3180@build.opensuse.org>
W: Failed to fetch http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04/Release.gpg  The following signatures were invalid: EXPKEYSIG 5A7D1D38BEB6D886 home:Horst3180 OBS Project <home:Horst3180@build.opensuse.org>
W: Some index files failed to download. They have been ignored, or old ones used instead.
➜  ~ apt-key list
/etc/apt/trusted.gpg
--------------------
pub   dsa1024 2007-03-08 [SC]
      4CCA 1EAF 950C EE4A B839  76DC A040 830F 7FAC 5991
uid           [ unknown] Google, Inc. Linux Package Signing Key <linux-packages-keymaster@google.com>
sub   elg2048 2007-03-08 [E]

pub   rsa4096 2016-04-12 [SC]
      EB4C 1BFD 4F04 2F6D DDCC  EC91 7721 F63B D38B 4796
uid           [ unknown] Google Inc. (Linux Packages Signing Authority) <linux-packages-keymaster@google.com>
sub   rsa4096 2016-04-12 [S] [expires: 2019-04-12]

pub   rsa2048 2015-03-27 [SC] [expired: 2017-06-04]
      D0E4 82AB 5DA8 5265 F9DE  BAE5 5A7D 1D38 BEB6 D886
uid           [ expired] home:Horst3180 OBS Project <home:Horst3180@build.opensuse.org>

/etc/apt/trusted.gpg.d/ubuntu-keyring-2012-archive.gpg
------------------------------------------------------
pub   rsa4096 2012-05-11 [SC]
      790B C727 7767 219C 42C8  6F93 3B4F E6AC C0B2 1F32
uid           [ unknown] Ubuntu Archive Automatic Signing Key (2012) <ftpmaster@ubuntu.com>

/etc/apt/trusted.gpg.d/ubuntu-keyring-2012-cdimage.gpg
------------------------------------------------------
pub   rsa4096 2012-05-11 [SC]
      8439 38DF 228D 22F7 B374  2BC0 D94A A3F0 EFE2 1092
uid           [ unknown] Ubuntu CD Image Automatic Signing Key (2012) <cdimage@ubuntu.com>