When saving to a “Navisworks file format (NWF), only a list with pointers to the files currently loaded is saved, along with the scene’s environment, the current view, clash results, if available, and favorite viewpoints (including redlines and comments). To open an NWF file, a Navisworks product is required, such as Review, Simulate, or Manage (not Freedom), as well as access to the original CAD files.” ^[1]

[1] The Massachusetts Port Authority, 2015. BIM Guidelines for Vertical and Horizontal Construction.