We found this bug when updating from 2010 to 2012 last week. Certain types of clusters will not update over datasocket or network-published shared variable. You will only get their default data. Here are the conditions that will cause the problem: The cluster contains an array of clusters The array of clusters is not the last item in the cluster The array of clusters is empty All three conditions must be fulfilled in order for the bug to appear. An AE was able to reproduce it and it has CAR #385089.