:~$ wget -O - https://content.runescape.com/downloads/ubuntu/runescape.gpg.key | sudo apt-key add -
--2017-09-07 15:06:58-- https://content.runescape.com/downloads/ubuntu/runescape.gpg.key
Resolving content.runescape.com (content.runescape.com)... 91.235.140.194, 91.235.140.195
Connecting to content.runescape.com (content.runescape.com)|91.235.140.194|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 942 [text/plain]
Saving to: ‘STDOUT’
- 100%[===================>] 942 --.-KB/s in 0s
2017-09-07 15:06:59 (5.66 MB/s) - written to stdout [942/942]
OK
byte@BONE:~$ sudo apt-get update
Hit:1 http://mirror.math.princeton.edu/pub/ubuntu zesty InRelease
Hit:2 http://mirror.math.princeton.edu/pub/ubuntu zesty-updates InRelease
Hit:3 http://mirror.math.princeton.edu/pub/ubuntu zesty-backports InRelease
Hit:4 http://mirror.math.princeton.edu/pub/ubuntu zesty-security InRelease
Hit:5 http://ppa.launchpad.net/appgrid/stable/ubuntu zesty InRelease
Hit:6 https://dl.winehq.org/wine-builds/ubuntu zesty InRelease
Hit:7 http://ppa.launchpad.net/audio-recorder/ppa/ubuntu zesty InRelease
Hit:8 http://repo.steampowered.com/steam precise InRelease
Hit:9 https://repo.skype.com/deb stable InRelease
Hit:10 http://ppa.launchpad.net/inkscape.dev/trunk/ubuntu zesty InRelease
Get:11 https://content.runescape.com/downloads/ubuntu trusty InRelease [2,236 B]
Hit:12 http://ppa.launchpad.net/unit193/encryption/ubuntu zesty InRelease
Ign:11 https://content.runescape.com/downloads/ubuntu trusty InRelease
Fetched 2,236 B in 0s (2,341 B/s)
Reading package lists... Done
W: GPG error: https://content.runescape.com/downloads/ubuntu trusty InRelease: The following signatures were invalid: AAC9264309E4D717441DB9527373B12CE03BEB4B
W: The repository 'https://content.runescape.com/downloads/ubuntu trusty InRelease' is not signed.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
byte@BONE:~$ sudo apt-key list
/etc/apt/trusted.gpg
--------------------
pub rsa2048 2015-10-13 [SC]
AAC9 2643 09E4 D717 441D B952 7373 B12C E03B EB4B
uid [ unknown] RuneScape Linux <noreply@jagex.com>
pub rsa1024 2013-08-25 [SC]
F9A8 B020 F741 A5B5 2B88 8A88 241F E697 3B76 5FAE
uid [ unknown] Launchpad PPA for appgrid
pub rsa2048 2016-06-22 [SC] [expires: 2021-06-21]
D404 0146 BE39 7250 9FD5 7FC7 1F30 45A5 DF75 87C3
uid [ unknown] Skype Linux Client Repository <se-um@microsoft.com>
sub rsa2048 2016-06-22 [E] [expires: 2021-06-21]
pub rsa4096 2015-11-23 [SC] [expires: 2025-11-20]
4A9E 0F43 60DC 0D17 956D 904E 818A 435C 5FCB F54A
uid [ unknown] Sebastian Lackner (WineHQ packages) <sebastian@fds-team.de>
sub rsa4096 2015-11-23 [E] [expires: 2025-11-20]
/etc/apt/trusted.gpg.d/audio-recorder_ubuntu_ppa.gpg
----------------------------------------------------
pub rsa4096 2015-08-30 [SC]
42EF 41ED 9813 B713 D4F1 F06D 5CF1 2638 ACF9 669F
uid [ unknown] Launchpad PPA for Team audio-recorder
/etc/apt/trusted.gpg.d/inkscape_dev_ubuntu_stable.gpg
-----------------------------------------------------
pub rsa1024 2011-06-13 [SC]
22C4 8501 4660 3F3D B0ED 0047 9DA4 BD18 B9A0 6DE3
uid [ unknown] Launchpad PPA for Inkscape Developers
/etc/apt/trusted.gpg.d/inkscape_dev_ubuntu_trunk.gpg
----------------------------------------------------
pub rsa1024 2011-06-13 [SC]
22C4 8501 4660 3F3D B0ED 0047 9DA4 BD18 B9A0 6DE3
uid [ unknown] Launchpad PPA for Inkscape Developers
/etc/apt/trusted.gpg.d/steam.gpg
--------------------------------
pub rsa2048 2012-12-07 [SC]
BA18 16EF 8E75 005F CF5E 27A1 F24A EA9F B054 98B7
uid [ unknown] Valve Corporation <linux@steampowered.com>
sub rsa2048 2012-12-07 [E]
/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>
/etc/apt/trusted.gpg.d/unit193_ubuntu_encryption.gpg
----------------------------------------------------
pub rsa1024 2012-11-21 [SC]
3BFB 8E06 536B 8753 AC58 A4A3 0364 7209 B58A 653A
uid [ unknown] Launchpad PPA for Unit 193