The BAT tool Gmax from Autodesk is no longer available from its official web site. No more info is offered at this point on why they have quit distributing it, but it isn’t too far fetched to believe they are interested into drawing more attention, and thus income, to their commercial and more powerful product 3ds Max.
If you’re still interested in it there are other ways of still obtaining it, still legally we assume:
Happy BATting. 😉