Good you mention this.
I wrote the document at
http://www.graphisoft.com/support/archicad/archiguide/UseofAUTOTEXTinPM.html
But it seems there are new Autotext items in PM9 so I will need to update this page.
I think this variable will give you the name of the ArchiCAD file the drawing data come from.
I believe it will work only if the text <ACFILENAME> is either included in the drawing placed on the Layout, or you select a placed drawing on the Layout, select it as an Automatic text Reference in its local menu (right-click-accessed), and AutoText entries will take data from that drawing. This worked for me. In this latter case you will see that the Text Tool will display something like <ACFILENAME_R><D7B93421-C3B1-4A01-BEA4-38BEF863B721> instead of <ACFILENAME>.
If you just place such an AutoText item on the Layout on its own without it being part of a drawing (which comes from an AC file) or being linked to a drawing as a reference (which also comes from an AC file), then it will not give you a correct value, but the text "Undefined AC File Name".
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