/usr/include/Inventor/nodekits/ is in inventor-dev 2.1.5-10-16ubuntu1.
This file is owned by root:root, with mode 0o755.
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/usr/include/Inventor/nodekits/SoAppearanceKit.h
/usr/include/Inventor/nodekits/SoBaseKit.h
/usr/include/Inventor/nodekits/SoCameraKit.h
/usr/include/Inventor/nodekits/SoInteractionKit.h
/usr/include/Inventor/nodekits/SoLightKit.h
/usr/include/Inventor/nodekits/SoNodeKit.h
/usr/include/Inventor/nodekits/SoNodeKitListPart.h
/usr/include/Inventor/nodekits/SoNodekitCatalog.h
/usr/include/Inventor/nodekits/SoNodekitParts.h
/usr/include/Inventor/nodekits/SoSceneKit.h
/usr/include/Inventor/nodekits/SoSeparatorKit.h
/usr/include/Inventor/nodekits/SoShapeKit.h
/usr/include/Inventor/nodekits/SoSubKit.h
/usr/include/Inventor/nodekits/SoWrapperKit.h