/usr/share/acl2-6.3/books/taspi/code/ is in acl2-books 6.3-5.
This file is owned by root:root, with mode 0o755.
..
/usr/share/acl2-6.3/books/taspi/code/brlens/
/usr/share/acl2-6.3/books/taspi/code/brlens/brlens.o
/usr/share/acl2-6.3/books/taspi/code/brlens/trees-with-brlens.o
/usr/share/acl2-6.3/books/taspi/code/build/
/usr/share/acl2-6.3/books/taspi/code/build/build-term-guards.o
/usr/share/acl2-6.3/books/taspi/code/build/build-term.o
/usr/share/acl2-6.3/books/taspi/code/fringes/
/usr/share/acl2-6.3/books/taspi/code/fringes/fringes-guards.o
/usr/share/acl2-6.3/books/taspi/code/fringes/fringes-props.o
/usr/share/acl2-6.3/books/taspi/code/fringes/fringes.o
/usr/share/acl2-6.3/books/taspi/code/gen-helper/
/usr/share/acl2-6.3/books/taspi/code/gen-helper/bdd-functions.o
/usr/share/acl2-6.3/books/taspi/code/gen-helper/extra.o
/usr/share/acl2-6.3/books/taspi/code/gen-helper/fast-lists.o
/usr/share/acl2-6.3/books/taspi/code/gen-helper/sets.o
/usr/share/acl2-6.3/books/taspi/code/gen-helper/top.o
/usr/share/acl2-6.3/books/taspi/code/gen-trees/
/usr/share/acl2-6.3/books/taspi/code/gen-trees/app-rev-lists.o
/usr/share/acl2-6.3/books/taspi/code/gen-trees/btrees-bdds-sets.o
/usr/share/acl2-6.3/books/taspi/code/gen-trees/btrees-bdds.o
/usr/share/acl2-6.3/books/taspi/code/gen-trees/btrees.o
/usr/share/acl2-6.3/books/taspi/code/gen-trees/sets-lists-trees.o
/usr/share/acl2-6.3/books/taspi/code/gen-trees/top.o
/usr/share/acl2-6.3/books/taspi/code/gen-trees/tree-predicates.o
/usr/share/acl2-6.3/books/taspi/code/replete/
/usr/share/acl2-6.3/books/taspi/code/replete/replete-guards.o
/usr/share/acl2-6.3/books/taspi/code/replete/replete-helper.o
/usr/share/acl2-6.3/books/taspi/code/replete/replete.o
/usr/share/acl2-6.3/books/taspi/code/sequences/
/usr/share/acl2-6.3/books/taspi/code/sequences/align.o
/usr/share/acl2-6.3/books/taspi/code/sequences/p-inform.o
/usr/share/acl2-6.3/books/taspi/code/sequences/seqs.o
/usr/share/acl2-6.3/books/taspi/code/tree-manip/
/usr/share/acl2-6.3/books/taspi/code/tree-manip/insertion-based-sort.o
/usr/share/acl2-6.3/books/taspi/code/tree-manip/merge-based-sort.o
/usr/share/acl2-6.3/books/taspi/code/tree-manip/mv-root.o
/usr/share/acl2-6.3/books/taspi/code/tree-manip/quicksort.o
/usr/share/acl2-6.3/books/taspi/code/tree-manip/sort-help.o
/usr/share/acl2-6.3/books/taspi/code/tree-manip/top.o