Before revision:  The goal of this paper is to introduce the UPL problem, describe the STAM architecture , and evaluate the latter in the UPL context.
After revision:  We evaluate STAM representations using clustering and classification tasks, relying on limited labeled data for the latter. Even though there are no prior approaches that are directly applicable to the UPL problem, describe the STAM architecture , and evaluate the latter in the UPL context.