/usr/include/ITK-4.10/itksys/ is in libinsighttoolkit4-dev 4.10.1-dfsg1-1.1+b1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/ITK-4.10/itksys/Base64.h
/usr/include/ITK-4.10/itksys/CommandLineArguments.hxx
/usr/include/ITK-4.10/itksys/Configure.h
/usr/include/ITK-4.10/itksys/Configure.hxx
/usr/include/ITK-4.10/itksys/Directory.hxx
/usr/include/ITK-4.10/itksys/DynamicLoader.hxx
/usr/include/ITK-4.10/itksys/Encoding.h
/usr/include/ITK-4.10/itksys/Encoding.hxx
/usr/include/ITK-4.10/itksys/FStream.hxx
/usr/include/ITK-4.10/itksys/Glob.hxx
/usr/include/ITK-4.10/itksys/MD5.h
/usr/include/ITK-4.10/itksys/Process.h
/usr/include/ITK-4.10/itksys/RegularExpression.hxx
/usr/include/ITK-4.10/itksys/SharedForward.h
/usr/include/ITK-4.10/itksys/String.hxx
/usr/include/ITK-4.10/itksys/System.h
/usr/include/ITK-4.10/itksys/SystemInformation.hxx
/usr/include/ITK-4.10/itksys/SystemTools.hxx
/usr/include/ITK-4.10/itksys/auto_ptr.hxx
/usr/include/ITK-4.10/itksys/hash_fun.hxx
/usr/include/ITK-4.10/itksys/hash_map.hxx
/usr/include/ITK-4.10/itksys/hash_set.hxx
/usr/include/ITK-4.10/itksys/hashtable.hxx