/usr/share/java/saxonb-ant.jar is in libsaxonb-java 9.1.0.8+dfsg-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/saxonb-ant-9.1.0.8+dfsg.jar
/usr/share/java/saxonb-ant-9.1.0.8+dfsg.jar