adam.johnson
Just so I'm clear on your requirements.. You have 2 separate CAD computers currently running in your office, one has a standalone license of PDS Prem installed on it and the other PDS Ultimate, is that correct? When you need to go into the field you would like to take a laptop and have the correct software on it, is that correct?
So to answer your question, 2 suites can not be installed on the same machine. The first installation of the suite trumps the 2nd one. Meaning if you installed Prem suite first and then Ultimate, Inventor Pro would not get installed because Inventor is already installed. Although there is some overlap in the software, using the same suite license at the same time will violate your agreement with Autodesk. Which could lead to a fines and etc.. 
As Curtis_Waguespack pointed out you could transfer the license onto the laptop when needed but the problem here is that you would always have to un-install and reinstall the correct suite on the laptop prior to transferring the license. The same holds true if you considered the laptop license to be used as a home use. But home use consideration can only occur if you have a active maintenance subscription.
I assume when you go into the field there's only 1 or 2 applications you need from the suite, is that correct? I know that you didn't want to purchase any more license but if you went the desktop subscription path (no longer can you buy standalong license) you could rent only the required products that you need (and install them on the laptop). Just a thought...
Mark Lancaster
& Autodesk Services MarketPlace Provider
Autodesk Inventor Certified Professional & not an Autodesk Employee
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