/usr/share/acl2-6.3/books/coi/osets/ is in acl2-books-certs 6.3-5.
This file is owned by root:root, with mode 0o755.
..
/usr/share/acl2-6.3/books/coi/osets/computed-hints.cert
/usr/share/acl2-6.3/books/coi/osets/conversions.cert
/usr/share/acl2-6.3/books/coi/osets/extras.cert
/usr/share/acl2-6.3/books/coi/osets/fast.cert
/usr/share/acl2-6.3/books/coi/osets/instance.cert
/usr/share/acl2-6.3/books/coi/osets/listsets.cert
/usr/share/acl2-6.3/books/coi/osets/map.cert
/usr/share/acl2-6.3/books/coi/osets/membership.cert
/usr/share/acl2-6.3/books/coi/osets/multiappend.cert
/usr/share/acl2-6.3/books/coi/osets/multicons.cert
/usr/share/acl2-6.3/books/coi/osets/outer.cert
/usr/share/acl2-6.3/books/coi/osets/primitives.cert
/usr/share/acl2-6.3/books/coi/osets/quantify.cert
/usr/share/acl2-6.3/books/coi/osets/set-order.cert
/usr/share/acl2-6.3/books/coi/osets/set-processor.cert
/usr/share/acl2-6.3/books/coi/osets/sets.cert
/usr/share/acl2-6.3/books/coi/osets/sort.cert