/usr/include/Inventor/engines/ is in libcoin80-dev 3.1.4~abc9f50-4ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/Inventor/engines/SoBoolOperation.h
/usr/include/Inventor/engines/SoCalculator.h
/usr/include/Inventor/engines/SoCompose.h
/usr/include/Inventor/engines/SoComposeMatrix.h
/usr/include/Inventor/engines/SoComposeRotation.h
/usr/include/Inventor/engines/SoComposeRotationFromTo.h
/usr/include/Inventor/engines/SoComposeVec2f.h
/usr/include/Inventor/engines/SoComposeVec3f.h
/usr/include/Inventor/engines/SoComposeVec4f.h
/usr/include/Inventor/engines/SoComputeBoundingBox.h
/usr/include/Inventor/engines/SoConcatenate.h
/usr/include/Inventor/engines/SoCounter.h
/usr/include/Inventor/engines/SoDecomposeMatrix.h
/usr/include/Inventor/engines/SoDecomposeRotation.h
/usr/include/Inventor/engines/SoDecomposeVec2f.h
/usr/include/Inventor/engines/SoDecomposeVec3f.h
/usr/include/Inventor/engines/SoDecomposeVec4f.h
/usr/include/Inventor/engines/SoElapsedTime.h
/usr/include/Inventor/engines/SoEngine.h
/usr/include/Inventor/engines/SoEngineOutput.h
/usr/include/Inventor/engines/SoEngines.h
/usr/include/Inventor/engines/SoFieldConverter.h
/usr/include/Inventor/engines/SoGate.h
/usr/include/Inventor/engines/SoHeightMapToNormalMap.h
/usr/include/Inventor/engines/SoInterpolate.h
/usr/include/Inventor/engines/SoInterpolateFloat.h
/usr/include/Inventor/engines/SoInterpolateRotation.h
/usr/include/Inventor/engines/SoInterpolateVec2f.h
/usr/include/Inventor/engines/SoInterpolateVec3f.h
/usr/include/Inventor/engines/SoInterpolateVec4f.h
/usr/include/Inventor/engines/SoNodeEngine.h
/usr/include/Inventor/engines/SoOnOff.h
/usr/include/Inventor/engines/SoOneShot.h
/usr/include/Inventor/engines/SoOutputData.h
/usr/include/Inventor/engines/SoSelectOne.h
/usr/include/Inventor/engines/SoSubEngine.h
/usr/include/Inventor/engines/SoSubNodeEngine.h
/usr/include/Inventor/engines/SoTexture2Convert.h
/usr/include/Inventor/engines/SoTimeCounter.h
/usr/include/Inventor/engines/SoTransformVec3f.h
/usr/include/Inventor/engines/SoTriggerAny.h