While experimental research on social dilemmas focuses on the distribution of gains, we analyze social preferences in the case of losses. In this experimental study, the participants share a loss in a Nash bargaining game, but waiting time, instead of monetary losses, serves as an incentive. Further, we assume that the participants prefer less, rather than more, waiting time. Our experiment consists of four versions of the Nash bargaining game to allow for a comparison of four classical negotiation concepts (Nash, equal loss, equal gain, and Kalai-Smorodinsky) and an equal split of the overall waiting time. Our experimental evidence shows that an equal split better predicts the outcome of a Nash bargaining game involving losses than classical concepts do. Furthermore, the findings support that the participants resort to equal splits at the cost of their overall welfare. (C) 2014 Elsevier B.V. All rights reserved.