TCF 2.3 Support - Disclosed Vendors Segment

[osazos]

Hi,

This library currently does not support TCF 2.3, which introduced a mandatory Disclosed Vendors segment. The current implementation only parses the Core String segment and ignores additional segments, making it non-compliant with TCF 2.3 requirements.

TCF 2.3 made the Disclosed Vendors segment mandatory to resolve ambiguity about whether vendors (especially those declaring only Special Purposes) were actually disclosed to users. The segment is needed to verify vendor legitimacy before allowing data processing.

Question

Is there a plan to add TCF 2.3 support to this library? This would involve:

• Parsing the mandatory Disclosed Vendors segment (second segment in TC strings)
• Exposing vendor disclosure information via the API
• Maintaining backward compatibility with TCF 2.0/2.2 strings

References

• TCF 2.3 Specification
• Version History - TCF 2.3 (April 2025)
• Disclosed Vendors Segment Specification

[alkmc]

@SyntaxNode @bsardo @hhhjort
As Prebid Server maintainers, do you know who maintains this project?
TCF 2.3 is an urgent issue for the ad ecosystem.

[peczenyj]

I was about to submit a pull request to add support to TCF 2.3, but since all of my previous pull requests receive no feedback, I think it is best switch to another implementation that is compliant with TCF 2.3 :/

[Katarzyna-B]

Hi everyone,

I also rely on this library and recently started working with TCF 2.3.
I saw that support for the Disclosed Vendors segment is still missing.

Before doing anything on my side, I just wanted to ask if there is already
ongoing work or a branch for TCF 2.3 that I could help with or support.

If there is any way I can contribute (implementation, testing, reviewing),
I’m happy to assist and coordinate with whoever is already looking into it.

Thanks!

CC: @peczenyj

[peczenyj]

hey @Katarzyna-B I dont have anything ready, but if I start something I will let you known

[Katarzyna-B]

@peczenyj thank you for your PR. I checked it and added some comments.

[osazos]

Hi @Katarzyna-B thank you for your quick review. I'll be able to work on it tomorrow.

[Katarzyna-B]

@osazos when do you plan to merge the changes to the community library -> https://github.com/prebid/go-gdpr/
I saw only that it was merge to fork one https://github.com/onfocusio/go-gdpr

[osazos]

@osazos when do you plan to merge the changes to the community library -> https://github.com/prebid/go-gdpr/ I saw only that it was merge to forg one https://github.com/onfocusio/go-gdpr

Hi @Katarzyna-B I don't have the rights to do that.

[Katarzyna-B]

@osazos do you know who should we ask for it?

[Katarzyna-B]

@dbemiller , @hhhjort maybe you have permission to do it?

[bsardo]

Hello everyone. I will bring this up for discussion at the next Prebid Server PMC tomorrow and I will get some reviewers from the community next week to look at the corresponding PR.