/usr/lib/x86_64-linux-gnu/libusb.so is in libusb-dev 2:0.1.12-31.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2
/* GNU ld script. */ GROUP ( /lib/x86_64-linux-gnu/libusb-0.1.so.4.4.4 )