The Open Radio Access Network (O-RAN) introduces openness and intelligence into the existing, tightly-coupled RAN ecosystem. Openness promotes collaboration among various vendors to provide diverse components (hardware, software, or both) for the RAN ecosystem, while intelligence handles complex network activities using Artificial Intelligence (AI). Although O-RAN design addresses many issues in traditional RANs, such as vendor lock-in, lack of flexibility, and limited innovation, it raises several management and security concerns related to collaboration, access management, privacy, trust, and availability. Distributed Ledger Technologies (DLTs) offer a viable method of establishing trust among entities, managing resources efficiently, and automating complex network tasks. Several DLT properties, such as distributed architecture, high automation through smart contracts, immutability, and transparency, could position DLT-based ideas as game changers in a multi-vendor O-RAN ecosystem. Furthermore, this technology has the potential to introduce new business models and establish secure and trusted micro-payments among vendors and network participants. In this paper, we first present a taxonomy for discussing existing O-RAN challenges. Based on the taxonomy, we then examine the possibility of incorporating DLT-based solutions in O-RAN architecture to address these challenges.