The EOSC EDEN project, an EU-funded initiative, is continuing its webinar series to share key results and insights from its work on advancing digital preservation strategies across Europe. At the heart of EOSC EDEN lies the ambition to develop a framework for identifying research data that should be prioritised for long-term digital preservation at both European and national levels. In this fourth seminar, we will present the findings from the survey run by EOSC EDEN between May and July 2025. The survey investigated current practices in digital preservation, and the guidance documents that inform these practices. Survey questions interrogated long-term preservation across different domains and organisation types, and identified issues that potentially affect how preservation and the findability, accessibility, interoperability, and reusability of digital data objects may change over time.