/usr/lib/x86_64-linux-gnu/libfosgra.so is in fosfat-dev 0.4.0-13-ged091bb-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libfosgra.so.0
/usr/lib/x86_64-linux-gnu/libfosgra.so.0