Individual Sovereignty and Decentralized Marketplaces are a natural occurrence in the DataGrid Blockchain (DGB).
Individual Sovereignty, is achieved through the account and object structure in DGB via XBOM. Every account can have a globally uniqueID and all assets owned by the account are subsets of the UniqueID. This means that any access to any of YOUR state, data, assets, medical records etc. can ONLY be accessed if you give explicit permission.
For Decentralize Multi-sided Marketplaces, again we look at the XBOM tech as it allows an account to transfer an object from one account to another with no intermediary. Now you can list items for offer in an open marketplace such as an Amazon, E-bay etc. There is no custodialship of the asset and all transfers of assets between accounts is direct without intermediaries.