Occasionally I hear from a customer who has purchased new licenses but wants to use an older version of Softimage (because they are mid-project and don’t want to switch versions right now). For example, I recently heard from a Softimage customer who had purchased some additional 2012 licenses, but wanted to use them to run 2011.

The Autodesk licensing is not like the old Softimage licensing (where XSI 4.2 would run with a 4.0, 5.0, 6.0, or 7.0 license).

Previous version usage (the ability to run older versions of the software) is a Subscription benefit. If you buy licenses without Subscription, those licenses will run only one version of the software. For example, if you buy some Softimage 2012 licenses without Subscription, those licenses won’t run 2011 (or 2010 or 7.5).

When you are on Subscription, a 2012 license also includes a 2011 license, a 2010 license, and a 7.5 license. In a network license file, this looks like this:

 
PACKAGE 78900SFTIMA_F adskflex 1.000 COMPONENTS="85705SFTIM_2012_0F \
                85563SFTIM_2011_0F 84000SFTIM_2010_0F 78600SFTIM_7_5F" \

You’ll also see something like this in the Perform Status Enquiry output (in LMTOOLS):

 
Users of 85705SFTIM_2012_0F:  (Total of 2 licenses issued;  Total of 0 licenses in use)
Users of 85563SFTIM_2011_0F:  (Total of 2 licenses issued;  Total of 0 licenses in use)
Users of 84000SFTIM_2010_0F:  (Total of 2 licenses issued;  Total of 0 licenses in use)
Users of 78600SFTIM_7_5F:  (Total of 2 licenses issued;  Total of 0 licenses in use)

As far as I know, you can’t buy old licenses when a new version is available. There may be a short period of time after a new release when the previous version is still available for purchase, but that would be only for a few months.