/usr/share/maven-repo/com/martiansoftware/ is in nailgun 0.9.3-2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/maven-repo/com/martiansoftware/nailgun-all/
/usr/share/maven-repo/com/martiansoftware/nailgun-all/0.9.3-SNAPSHOT/
/usr/share/maven-repo/com/martiansoftware/nailgun-all/0.9.3-SNAPSHOT/nailgun-all-0.9.3-SNAPSHOT.pom
/usr/share/maven-repo/com/martiansoftware/nailgun-all/debian/
/usr/share/maven-repo/com/martiansoftware/nailgun-all/debian/nailgun-all-debian.pom
/usr/share/maven-repo/com/martiansoftware/nailgun-server/
/usr/share/maven-repo/com/martiansoftware/nailgun-server/0.9.3-SNAPSHOT/
/usr/share/maven-repo/com/martiansoftware/nailgun-server/0.9.3-SNAPSHOT/nailgun-server-0.9.3-SNAPSHOT.jar
/usr/share/maven-repo/com/martiansoftware/nailgun-server/0.9.3-SNAPSHOT/nailgun-server-0.9.3-SNAPSHOT.pom
/usr/share/maven-repo/com/martiansoftware/nailgun-server/debian/
/usr/share/maven-repo/com/martiansoftware/nailgun-server/debian/nailgun-server-debian.jar
/usr/share/maven-repo/com/martiansoftware/nailgun-server/debian/nailgun-server-debian.pom