The Internet of Things (IoT) is more and more omnipresent. The greater values of the IoT can be realized by enabling data sharing between different stakeholders. However, one of the biggest challenges is ensuring security and enabling trust for IoT data sharing. In this paper, we identify state-of-the-art (SotA) approaches and techniques for secure IoT data sharing. We present high-level results emphasizing the SotA trend and revealing the most addressed domains, as well as more in-depth details such as procedures and methods used to preserve security in the data sharing environment. The blockchain technology, smart contracts, and InterPlanetary File System (IPFS) are among the most widely used approaches. As today’s solutions explore a more decentralized approach to data sharing, there are several aspects to consider. Based on the findings, we have identified potential research directions for future work, including the differences between public and private blockchains, the combinat (More)