Access control and data sharing in the Industrial Internet of Things (IIoT) is a critical research area focused on ensuring secure, reliable, and efficient communication among industrial devices, sensors, and systems. Research papers in this domain explore frameworks and protocols for role-based, attribute-based, and context-aware access control, as well as secure and privacy-preserving data sharing mechanisms in heterogeneous IIoT environments. Key contributions include blockchain-enabled decentralized access management, lightweight cryptographic schemes for resource-constrained devices, and edge/fog-assisted enforcement of security policies for real-time industrial applications. Recent studies also address challenges such as scalability, interoperability, dynamic industrial workflows, and compliance with regulatory standards. By integrating AI-driven monitoring, trust evaluation, and secure communication protocols, research in access control and data sharing in IIoT aims to enable resilient, adaptive, and secure industrial networks that support smart manufacturing, predictive maintenance, and operational efficiency.