<p>Open banking is a new emerging paradigm to leverage our banking data so that third parties can enable value-added services. The regulations required for open banking are only at their infancy stage. Although some countries have started using open banking, it lacks many security considerations. Open banking requires sharing a large amount of financial data flowing from banks to third parties that provide financial services to their customers. However, if there were no measures to control data sharing (or course-grained data sharing), there could be security and privacy issues along with increased impact as a result of data breaches or misuses. Fine-grained data sharing and consent mechanisms solve those issues by reducing the amount of data being shared. In this work, we design a data sharing framework that can enable fine-grained data sharing in an efficient manner. Our framework ensures that only the least amount of data required to provide the service is shared and that access to said data is limited while also ensuring that consent is provided before any data sharing occurs. We designed a new entity in open banking to implement those requirements and to facilitate communication between other entities such as banks and third parties.</p>