/usr/lib/x86_64-linux-gnu/libantlr3c.so is in libantlr3c-dev 3.2-2build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libantlr3c-3.2.so.0.0.0
/usr/lib/x86_64-linux-gnu/libantlr3c-3.2.so.0.0.0