/usr/lib/x86_64-linux-gnu/libotf.a is in libotf-trace-dev 1.12.5+dfsg-1build2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libopen-trace-format.a
/usr/lib/x86_64-linux-gnu/libopen-trace-format.a