Blue-Cloud partners and collaborators gathered in Brussels from 5 to 7 November 2025 for a three-day series of strategic and technical sessions, anchored by the Third Federation Workshop. The event took place just after the EOSC Symposium, as Blue-Cloud is supporting the creation of a Thematic Node within the EOSC Federation under the name "EOSC Node Digital Twin of the Ocean". On 5th November afternoon, the event counted with two hands-on sessions exploring the EOSC Marine Node core and thematic services and cross-node use cases. These interactive demonstrations offered participants a closer look at the technical developments powering Blue-Cloud’s federated services. On 6th November, the Third Federation Workshop brought together project partners, EOSC stakeholders, and Synergy Projects for a full day of in-depth discussion and exchange. The agenda featured an opening overview of key takeaways from the EOSC Symposium, followed by a sequence of panel discussions covering core services, the connection between EOSC and EDITO, the practical challenges of building a federated approach, and capacity-building efforts. Official event page: https://blue-cloud.org/events/blue-cloud-2026-third-federation-workshop