/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/ is in libeigen3-dev 3.2.2-3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/AlignedBox.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/All.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/AngleAxis.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/Hyperplane.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/ParametrizedLine.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/Quaternion.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/Rotation2D.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/RotationBase.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/Scaling.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/Transform.h
/usr/include/eigen3/Eigen/src/Eigen2Support/Geometry/Translation.h