/usr/share/perl5/Dpkg/Source/ is in libdpkg-perl 1.19.0.5ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/perl5/Dpkg/Source/Archive.pm
/usr/share/perl5/Dpkg/Source/Functions.pm
/usr/share/perl5/Dpkg/Source/Package/
/usr/share/perl5/Dpkg/Source/Package.pm
/usr/share/perl5/Dpkg/Source/Package/V1.pm
/usr/share/perl5/Dpkg/Source/Package/V2.pm
/usr/share/perl5/Dpkg/Source/Package/V3/
/usr/share/perl5/Dpkg/Source/Package/V3/Bzr.pm
/usr/share/perl5/Dpkg/Source/Package/V3/Custom.pm
/usr/share/perl5/Dpkg/Source/Package/V3/Git.pm
/usr/share/perl5/Dpkg/Source/Package/V3/Native.pm
/usr/share/perl5/Dpkg/Source/Package/V3/Quilt.pm
/usr/share/perl5/Dpkg/Source/Patch.pm
/usr/share/perl5/Dpkg/Source/Quilt.pm