/usr/lib/libGraphicsMagick.so.3 is in libgraphicsmagick3 1.3.18-1ubuntu3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libGraphicsMagick.so.3.11.0
/usr/lib/libGraphicsMagick.so.3.11.0