E015 [ www.e015.regione.lombardia.it ] is the institutional Data Space managed by Lombardy Region in Italy. Every local public body or private company can become part of the E015 Data Space, signing a free-membership contract with Lombardy Region: according to this legal framework, every player can list own REST APIs within a common catalog, or can ask for APIs listed by other players; every player can freely decide to accept or decline the request for using own APIs, so that data sovereignty and business competitivity are preserved, enabling only win-win scenarios. Data exchange is performed peer-to-peer, without a technical E015 intermediary infrastructure; E015 consists of just a legal framework, operational processes led by an online workflow, and it is operatively managed by the Technical Management Board by Lombardy Region with the Scientific Advisory of Cefriel [ www.cefriel.com/news-en/the-history-of-the-e015-digital-ecosystem/?lang=en ]. E015 was founded in 2012 and it has enabled more than 600 public-private data exchange relationships in various sectors, for example:
- In order to mitigate overtourism, Lombardy Region is promoting the less famous destinations, communicating through main regional channels [ www.in-lombardia.it/en ] all the local events thanks to interoperability by E015 with local touristic portals.
- In order to promote sustainable tourism, in Valchiavenna it is promoted by E015 the use of multi-modal public transport to reach bike routes [ www.valchiavennabike.it/en/ ].
- In order to promote the safety of people, real-time information about Civil Protection Alerts are spread by E015 in various communication channels, for example town municipalities portals [ www.comune.rho.mi.it/en-us/linea-diretta/bollettino-allerta-meteo ].

The main goals are the creation of new public-private data exchange relationships promoted by E015, with a specific focus on the adoption of E015 in tourism, mobility, and safety sectors, during the upcoming Milano Cortina 2026 Winter Olympic Games. E015 experience and lessons learned, legal framework and governance model are going to be proposed as a multi-years Best Practice for the non-technical approach in the creation of European Data Spaces.