
I thought the number of different methods proposed was interesting, so using a BricsCAD generated drawing I undertook some tests. Of course you could also try and convince your client to by BricsCAD :-) However this may result in loss of drawing fidelity. Down Convert your drawings to a version prior to R14 (can use _ETRANSMIT).Educate/Inform your client, and tell them how they can control the messaging from their end.In later versions they seem to have toned it down, so you can turn it completely off. If you have AutoCAD circa 2007 you will get much more obtrusive messaging and alerts. You will see from the second article that it also drove AutoCAD users crazy when introduced. If your recipient is seeing these messages, you would need to explain what the message means, and how they can control it. In AutoCAD there is a variable called DWGCHECK that can be set to control what messaging is displayed when opening a non AutoDESK. More background on this can be found here: If it isn't it will notify the user to the fact. AutoDESK use this to identify whether the drawing has been produced by an AutoDESK product, and from this whether it is a "Trusted Drawing" or not.

They copyrighted this object, which prevents anyone else from using it (I believe there was a lawsuit against the ODA to do with this). My understanding is that around R14 of AutoCAD, AutoDESK introduced a header object into the DWG file to identify it as a "RealDWG". It is something you need to educate the AutoCAD recipient on.

Short answer is that there is nothing much you can do to "fix" this from your side.
