As identified in the previous section, there are several reasons why you may not be legally (or ethically) allowed to share your data, but even if you can, it's not always clear to someone else if they can reuse your data in their own work.
The best way to make it clear to others that they are allowed to use and reuse your data is to assign a license to it. Think of it as a permission slip explicitly letting others know under what conditions they can (or cannot) use your data.
Probably the most widely recognized licenses available to the general public are Creative Commons licenses. Creative Commons provides an easy form to help you determine which license is appropriate for the conditions you want to apply for reuse of your data. Remember, check with your funder, your institution, and any other possible rights holders before you apply a license to your data.
In order for a data set to be considered "open data" a data set must be free for anyone to "access, use, modify, and share". The three Creative Commons licenses that allow for that are:
- CC-0: Technically this isn't a license, but a waiver. It allows the copyright holder to waive their interests in the data and place it fully in the public domain. Whenever possible, we recommend using CC-0 for your data.
- CC-BY: This license allows sharing and remixing with the caveat that the user gives proper attribution to you. This is the most restrictive license we support for open data.
- CC-BY-SA: This license is similar to CC-BY in that it requires attribution, but it places an additional restriction by requiring you to share any derivative work from the data, it must also be released under a CC-BY-SA license. We do NOT recommend this license for open data as it can lead to serious problems with license stacking. (Read more about license stacking in Primer 5.)
For more about Creative Commons licenses, check out the short video below.
VIDEO: Wanna Work Together?, Creative Commons (3:00 mins)