Licensing contributions for structured data are currently not listed on Commons.
All structured data from the file and property namespaces are available under the Creative Commons CC0 License. We need a message that states this clearly to users before they publish contributions. Commons will use the same text that Wikidata uses because it has already been reviewed and approved by the legal department, and it's useful to have this kind of language be consistent across projects.
It is clear to users on both File Pages and Upload Wizard that editing/adding structured data is a CC0 contribution.
The above message will be shown on edit unless the user permanently dismiss it by accepting those terms.
User flows & designs
Proposal is for the File Page message to operate in the same manner as Wikidata: when a user selects "edit" they will see the CC0 dialog, and accept the message to permanently dismiss the notice.
The CC0 message will work a little differently on Upload Wizard because there is no read/edit mode like File Page. Instead, the proposal is to show it on the Release Rights step, so all licensing information is grouped on the same step.
Screenshot of Wikidata's license popover