root@grey:~# apt-key list | grep -A 1 expired
pub 4096R/46925553 2012-04-27 [expired: 2020-04-25]
uid Debian Archive Automatic Signing Key (7.0/wheezy) <ftpmaster@debian.org>
--
pub 4096R/65FFB764 2012-05-08 [expired: 2019-05-07]
uid Wheezy Stable Release Key <debian-release@lists.debian.org>
--
pub 4096R/623DB0B8 2014-01-16 [expired: 2015-01-31]
uid Debian Ports Archive Automatic Signing Key (2014) <ftpmaster@debian-ports.org>
--
pub 4096R/C448326E 2015-01-27 [expired: 2016-02-01]
uid Debian Ports Archive Automatic Signing Key (2015) <ftpmaster@debian-ports.org>
apt-key adv --keyserver hkp://keyserver.ubuntu.com --recv-keys 46925553