Add license information in the GTFS schedule feed

[skalexch]

Summary

This proposal allows for describing license information in GTFS feeds.

1. It adds a field type, SPDX ID, that reference the SPDX identifier for standard licenses.
2. It adds a file licenses.txt that describes the SPDX license or provides a custom license URL for the whole feed, with the possibility of specifying the license information for specific files in other rows.

Describe the Problem

There has been a lot of conversation in the community regarding license information. It seems like most people agree on adding license information, and the main discussion was around the scope, i.e. can some files have different terms?

Previous conversations about license information, and there were some previously suggested options, mainly:

• A column in feed_info.txt that can be SPDX or URL if the license is custom.
• Multiple columns that can be specified by operator (agency_id) and even entity (filename).
• A column in feed_info.txt + a traditional LICENSE.txt file.

The full conversations can be found in the license proposal issue and a Google Groups thread.

Proposed Solution

The solution entails the addition of a file called licenses.txt, which lists the licenses for the whole feed as well as any specific files that might have a different license (e.g. shapes.txt). The license is specified either as an SPDX ID or as a custom URL.

The producer can choose to either:

• Create rows that specify the license for a specific file each.
• Create a row to specify the license for the whole feed, except for the files that were mentioned in other rows.

Type of change

GTFS Schedule

• Functional Change
• Non-Functional Change
• Documentation Maintenance

GTFS Realtime

• Specification Change
• Specification Change (Experimental Field)

Proposed Discussion Period

To put more eyes on this proposal, we propose a discussion period of at least two weeks.

Testing Details

• Consumer(s):
• Producer(s):
• Estimated Testing Period:

Proposal Update Tracker

Date	Update Description
(2026-02-03)	Discussion period opened

Checklist

• I have read and understood the GTFS Change process.
• I have read and understood the GTFS Guiding Principles.
• I understand the Role of Advocate and the Responsibilities attached to it.
• I have signed the Contributor License Agreement (CLA).
• I have ensured that this proposal is not covered by an existing Pull Request.

Examples

Simple feed with one standard license:

licensed_table_name	license_spdx_id	custom_license_url
	spdx_value

Simple feed with custom license:

licensed_table_name	license_spdx_id	custom_license_url
		custom_license_url

Feed with a standard license, shapes.txt has a custom license:

licensed_table_name	license_spdx_id	custom_license_url
	spdx_value
shapes.txt		custom_license_url_for_shapes

In this case,

• The license for shapes.txt is custom_license_for_shapes
• The rest of the feed has spdx_value

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[skinkie]

We would absolutely want to support this. But I think I cannot specify that no files may be added. So in order to do that the file must be added empty, and then applied CC-ND.

[skalexch]

@skinkie one solution could be assigning CC-ND to the whole feed by keeping `. Which would disallow the distribution of any work built on top of the feed. In this case, adding a file to the feed would be considered building on it.

We could modify the language in the proposal by saying: "If licensed_table_name is empty, the license apply to the feed itself and to all the tables inside."

[skinkie]

@skalexch another thing. Some licences like CC-BY and ODbL require attribution. I think an attribution attribute would make sense too.