Anchiornis, it's not dinosaurs/reptile?

In wikipedia says that Anchiornis include reptiles group. In National Geographic also says that Anchiornis is "dinosaurs four winged". Anchiornis's feathers is similiar with modern bird feather. Wings and feather are character of birds group, not reptiles. In addition, there are bird todays with leg-feathered like Anchiornis. Barn owl, snowy owl, frizzle chicken, sultans chincken, cochin, and some kind of pigeon known also have feathered foot. But, they are birds, not group of reptiles. So why Anchiornis include reptiles? Or sometimes people says Anchiornis are "transitional" and "dino four winged". Are chicken or snowy owl "transitional animals" or "dino four winged'?