/usr/lib/libOpenImageIO_Util.so.1.6 is in libopenimageio1.6 1.6.11~dfsg0-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libOpenImageIO_Util.so.1.6.11
/usr/lib/libOpenImageIO_Util.so.1.6.11