Like other software components, IoT things are likely to collaborate with each other in order to attain a desirable business goal. This sort of collaboration in a cyber-physical surrounding dictates a special transactional model that warrants further study and investigation. In this paper, we argue that the atomicity model (i.e., all or none execution) that is witnessed in other fields cannot be fully exercised in the context of IoT. To that end, a more relaxing model (semi-atomicity) is introduced and is more amenable to the various duties associated with things in terms of sensing, actuating, and communicating. These duties are carried out under different transactional properties. to which things bind. A case study along with a set of experiments demonstrate the benefits of semi-atomicity in the context of IoT.