How can a Tax Data Lake accelerate the digital transformation of corporate tax functions and lay the foundation for AI-driven applications? In the article ”Weg von den Inseln, hin zum See - ein Data Lake für die Steuerfunktion” by Felix Fischer, Alexander Maedche, Christoph Spengel, Niklas Wagner, and Sarah Winter published in issue 46 of DER BETRIEB, we share practical insights from our cooperative research project "Agentic Tax Information Systems" conducted between by EnBW Energie Baden-Württemberg AG, the University of Mannheim, and the Karlsruhe Institute of Technology (KIT). The article highlights how tax-relevant data from fragmented IT systems and isolated applications can be integrated into a central Tax Data Lake and demonstrates concrete use cases illustrating its potential. The consolidated data foundation enables the integration of downstream systems, facilitates process automation, and supports automated reporting. Moreover, it lays the foundation for our LLM-based Data Assistant, which enables users in the finance function to retrieve and analyze information across multiple systems using natural language. Together, these use cases demonstrate how a modern data architecture can overcome existing IT silos and pave the way for increasingly intelligent, automated, and data-driven tax processes. 

Special thanks go to EnBW’s CFO unit, led by Thomas Kusterer, and particularly to Prof. Dr. Gerd Gutekunst and Achim Argus for their excellent collaboration and support throughout the cooperative research project.