[cartan]

PDF is Adobe owned, but nowadays it is also an open standard (in fact, a coworker of mine is in the PDF/A ISO committee, and I don’t work for Adobe), a well-defined file format. PDF is indeed a very complicated file format, but whether a PDF (or its pages) are multi-layered or not is a simple yes-or-no question. And if Adobe Reader, Foxit, and Inkscape all say there aren’t any, I am strongly inclined to believe them…:-)

[D-fendr]

I’m fine with a conclusion that the layers are created by Illustrator. I’m just not wanting to claim that for a fact on the basis of my own expertise.

What I know is that other, non forged files exhibit the same behaviour as this poster describes.