When organizations purchase information systems from IT vendors, they produce formal calls for ten-der (CFT) that specify, among other attributes, the required usability criteria of the systems. HCI re-search has concentrated on the IS purchaser organizations’ view and studied usability practices and criteria embedded into CFTs. However, IS vendors’ perspective is much less studied and especially the effects of characteristics of CFTs on IS vendors’ usability practices remain unexplored. We partic-ipated in a large tendering and experienced how the CFT introduced obstacles in the vendor’s usabil-ity work that needed workarounds, which may decrease system usability in context after the tendering and falsify the evaluation results of the purchaser. We identified obstacles arising from the tendering context, evaluation practices and usability measures. The joint effect of detailed usability test tasks and user performance measures published as well as a limited communication and time during the process were experienced as the most problematic and counterproductive in vendor’s usability work.