The railway signaling system is responsible for managing traffic and ensuring a safe distance between trains in all circumstances. Faced with growing demand for rail transport, renowned for its low carbon footprint, the traditional signaling system, based on the fixed block concept, is reaching its capacity limits. Future signaling systems, based on the moving block concept, aim to reduce the spacing between succeeding trains, thus optimizing the use of existing infrastructure. However, the full requirements for these systems are still under development and require further refinement before they can be considered as a viable and, above all, safe solution for European railways. In this context, European projects X2Rail-1 (2019), X2Rail-3 (2020) and X2Rail-5 (2022) provide detailed descriptions of the functional and safety requirements of these systems in structured natural language. This article presents a method for analyzing these requirements. The study relies on rule-based tools and custom scripts to extract, track, and visualize the evolution of these requirements. The identified requirement changes guided the update of the system’s functional architecture to align with the most recent specifications.