Mystery File-Type

I received a PDF Ad from a client yesteday that includes a filetype I have never seen before? When I open the PDF in Illustrator, their logo just appears as a. rectangle with an "X" thhrough it  in outline mode (like it is maybe a placed raster image). However there are no placed images or links in the file. If I select the rectangle and do a copy/paste into Photoshop, it pastes it as a Smart Object and I can scale it like a vector graphic. If I double-click the Smart Object, it launches and opens in Illustrator, but again no outlines in outline view?

I have never seen a scaleable vector graphic where you could not access the oulines to modify the artwork? What kind of file could this be?

See attached .AI file.