(xenial-amd64)root@nosferatu:/home/adconrad/xorg# grep '\.asc' xorg-server*dsc
 4d761e7fb1595637beb035c0b300e1b93d30fdb7 705 xorg-server_1.19.6.orig.tar.gz.asc
 d4672cc887a2037708dbc21e261fc1264d2808feb1f9d85b40ae7848fbb19443 705 xorg-server_1.19.6.orig.tar.gz.asc
 4708215dc9dd371ceee52c7760d7fc5c 705 xorg-server_1.19.6.orig.tar.gz.asc
(xenial-amd64)root@nosferatu:/home/adconrad/xorg# dpkg -l libdpkg-perl | grep ^i
ii  libdpkg-perl   1.18.4ubuntu1.3 all          Dpkg perl modules
(xenial-amd64)root@nosferatu:/home/adconrad/xorg# dpkg-source -x xorg-server_1.19.6*dsc
gpgv: Signature made Thu Feb 22 10:59:56 2018 MST using RSA key ID A88984DC
gpgv: Can't check signature: public key not found
dpkg-source: warning: failed to verify signature on ./xorg-server_1.19.6-1ubuntu2.dsc
dpkg-source: info: extracting xorg-server in xorg-server-1.19.6
dpkg-source: error: unrecognized file for a v1.0 source package: xorg-server_1.19.6.orig.tar.gz.asc
(xenial-amd64)root@nosferatu:/home/adconrad/xorg# apt-get install libdpkg-perl
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  dpkg-dev
Suggested packages:
  debian-keyring
Recommended packages:
  libalgorithm-merge-perl libfile-fcntllock-perl
The following packages will be upgraded:
  dpkg-dev libdpkg-perl
2 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
Need to get 779 kB of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] 
Get:1 http://us.archive.ubuntu.com/ubuntu xenial-proposed/main amd64 dpkg-dev all 1.18.4ubuntu1.4 [584 kB]
Get:2 http://us.archive.ubuntu.com/ubuntu xenial-proposed/main amd64 libdpkg-perl all 1.18.4ubuntu1.4 [195 kB]
Fetched 779 kB in 0s (1011 kB/s)     
(Reading database ... 15190 files and directories currently installed.)
Preparing to unpack .../dpkg-dev_1.18.4ubuntu1.4_all.deb ...
Unpacking dpkg-dev (1.18.4ubuntu1.4) over (1.18.4ubuntu1.3) ...
Preparing to unpack .../libdpkg-perl_1.18.4ubuntu1.4_all.deb ...
Unpacking libdpkg-perl (1.18.4ubuntu1.4) over (1.18.4ubuntu1.3) ...
Setting up libdpkg-perl (1.18.4ubuntu1.4) ...
Setting up dpkg-dev (1.18.4ubuntu1.4) ...
(xenial-amd64)root@nosferatu:/home/adconrad/xorg# dpkg-source -x xorg-server_1.19.6*dsc
gpgv: Signature made Thu Feb 22 10:59:56 2018 MST using RSA key ID A88984DC
gpgv: Can't check signature: public key not found
dpkg-source: warning: failed to verify signature on ./xorg-server_1.19.6-1ubuntu2.dsc
dpkg-source: info: extracting xorg-server in xorg-server-1.19.6
dpkg-source: info: unpacking xorg-server_1.19.6.orig.tar.gz
dpkg-source: info: applying xorg-server_1.19.6-1ubuntu2.diff.gz
dpkg-source: info: upstream files that have been modified: 
 xorg-server-1.19.6/.dir-locals.el
 xorg-server-1.19.6/config/dbus-api
 xorg-server-1.19.6/damageext/damageext.h
 xorg-server-1.19.6/doc/c-extensions
 xorg-server-1.19.6/fix-miregion
 xorg-server-1.19.6/fix-miregion-private
 xorg-server-1.19.6/fix-patch-whitespace
 xorg-server-1.19.6/fix-region
 xorg-server-1.19.6/hw/kdrive/Xkdrive.man
 xorg-server-1.19.6/hw/kdrive/fbdev/Xfbdev.man
 xorg-server-1.19.6/hw/xfree86/os-support/shared/platform_noop.c
 xorg-server-1.19.6/hw/xfree86/xkb/meson.build
 xorg-server-1.19.6/hw/xquartz/GL/glcontextmodes.c
 xorg-server-1.19.6/hw/xquartz/GL/glcontextmodes.h
 xorg-server-1.19.6/hw/xwin/winclipboard/internal.h
 xorg-server-1.19.6/xkb/XKM_file_format.txt