Welcome to Mozilla Science Lab's Open Data Primers!


License stacking

In Primer 3, we talked about assigning licenses to your data set to make it more clear to others how they can use your data. Knowing what terms the data you’re using is licensed under is essential for understanding conditions and stipulations of use, so one of the first things you should do is look for the license associated with the dataset you want to use.

The license affects how you can use and share the data, even if the data is available under an open license. For data, not all open licenses are created equal as attribution becomes increasingly complex as multiple datasets are combined, reused, and reused again.

The general rule, when combining or reusing data, is that derivative work must be licensed under the most restrictive license of all the contributing data sets. This can lead to a difficult-to-navigate situation called “license stacking” or “attribution stacking,” where each reuse of a dataset leads to more restrictive conditions. Watch this 5 minute video below about license stacking on open educational resources (OER) for examples of how this works.

VIDEO: Creating OER and Combining Licenses, TheOGRepository (4:56 mins)

Always license your data using the least restrictive license possible, to maximize the impact and reach of your work. Consult your librarian for help navigating more restrictive licenses.