Neither a Global Privacy Platform string nor a US Privacy string is read when the cloud decides the usage of a 51Did (51Degrees Identifier). The Model Terms for Marketing map the IAB Europe Transparency and Consent Framework and nothing else, so no section of either string says what the usage values say.
The Global Privacy Platform is the IAB Tech Lab container that carries several consent signals in one string, one section per signal. The US Privacy string is the older signal written for the California Consumer Privacy Act, which IAB Tech Lab deprecated on 31 January 2024 and tells its users to replace with the platform.
What Happens to a Request Carrying One🔗
A request whose only signal is one of these strings gets no usage from it. Nothing then asks for a 51Did, so the response carries no fodid section at all, no property, no reason and no warning, which is exactly what a request carrying no signal gets. That holds for every section a platform string can carry, the United States national section included, and under both of the names such a string travels under, being gpp and gppstring. The 51Degrees Prebid module sends it as gppstring.
A Transparency and Consent Framework string sent beside one is read exactly as it is read on its own, so a page whose consent platform emits both keeps working. That reading is Transparency and Consent Framework Strings.
Neither name is advertised in the service's evidence keys, so a client that builds its request from that list stops sending them, and the client script does not hand a platform string back to the page for its next call.
Why the Terms Decide This🔗
The usage inside a 51Did says what a recipient of the identifier may do with it, and that meaning comes from the Model Terms for Marketing rather than from 51Degrees. The text in force is version 2, at https://m4ow.uk/mtm/2.txt, with the scheme explained at https://m4ow.uk/mtm. Appendix 1 of that text maps the Transparency and Consent Framework's purposes onto standard marketing and personalized marketing, and maps no other signal, so a platform string can be a real signal and still say nothing a usage could be built from.
This is not a special case for the platform. A framework string that grants too little for either usage produces no identifier either, for the same reason, which is that the signal does not say what the usage values say.
Mapping the platform needs a new version of the Model Terms and a cloud release that reads it, so there is no setting on a resource key or a parameter on a request that turns this on.
If a Platform String Is All You Have🔗
Two routes lead to an identifier.
- Ask the visitor the Model Terms question. The Preference Management Platform asks it in the visitor's own language and the answer reaches the cloud as a stated usage. See The Preference Management Platform Answer and PMP (Preference Management Platform).
- Run a Transparency and Consent Framework platform. Its string is read as it always was, whether or not a platform string is sent beside it. See Transparency and Consent Framework Strings.
Where your own code decides the usage instead, it states the value on the request as id.usage and you own that mapping, which is the direct path under Setting the usage policy on 51Did (51Degrees Identifier). The two marketing usages still need the Special license key, and the Model Terms still govern what a recipient may do with the identifier that comes back.
Checking What a Service Reads🔗
Earlier releases of the cloud service read the European section of a platform string sent as gpp, so a page that relied on that gets no identifier once the service it calls has been upgraded. Ask the service what it reads.
The answer lists the evidence keys the service accepts. A service listing query.gpp still reads a platform string, and a service whose list does not carry that key reads none.
Find Out More🔗
- The consent string the cloud does read: Transparency and Consent Framework Strings
- The visitor's answer sent as a stated usage: The Preference Management Platform Answer
- The identifier, its inputs and its payload: 51Did (51Degrees Identifier)
- Passing the identifier into header bidding: Prebid
- The Model Terms for Marketing, version 2: https://m4ow.uk/mtm/2.txt
- The Model Terms for Marketing explainer: https://m4ow.uk/mtm
- IAB Tech Lab, the Global Privacy Platform: https://github.com/InteractiveAdvertisingBureau/Global-Privacy-Platform
- IAB Tech Lab, the US Privacy string: https://github.com/InteractiveAdvertisingBureau/USPrivacy
- IAB Europe, the Transparency and Consent Framework: https://iabeurope.eu/transparency-consent-framework/