Define where the collectively maintained data will sit on the data spectrum. Create or choose a clear data-sharing agreement or licence that provides rights to use the data in ways that maximises value while minimising potential harms. Ensure that the licence is clearly described and linked from any page that provides access to data.
There is a complex set of rights that apply to data and content. It is important that data is clearly licensed to enable reuse.
Collaborative maintenance projects might involved the creation of datasets that sit anywhere on the data spectrum. It is possible that a project might publish and share multiple datasets. For example, some sensitive data might only be shared with certain users or contributors; but other data might be openly licensed.
Some projects also choose to support multiple licences as part of a business model designed to make the project sustainable. For example, data might be openly available under a licence that requires attribution and sharing of changes, or it might be available under a more liberal licence under commercial terms.
Reusing existing standard licences helps users understand how data from the project can be combined with other sources.
Collaboratively maintained datasets are typically created so that they provide value to all stakeholders, so the licence that is chosen should be as open as possible.
The success of large, collaboratively maintained datasets such as OpenStreetMap is due to its open licensing. The fact that anyone can access, use and share data that has been contributed builds confidence that the data cannot later be switched to a more closed licence.
Lack of clarity around rights, eg because of the lack of a Clear Licencing has meant that some projects have struggled to become more open over time.