What are source.tid and source.fd in OpenRTB?
Answer
source.tid is a transaction ID that must be common across all participants in the bid request, so multiple exchanges auctioning the same impression (header bidding, for example) can be correlated and deduplicated. source.fd declares who makes the final impression sale decision: 0 means the exchange itself, 1 means an upstream source such as a header bidding wrapper, another exchange, or an ad server mixing direct and programmatic demand. Both are recommended fields on the Source object, which also hosts pchain and schain.
Fields in this answer
| Field | Type | Since | Status in 2.6 |
|---|---|---|---|
source.tid | string | 2.5 | Current |
source.fd | integer, recommended | 2.5 | Current |
Go deeper
More questions on privacy, identity, supply chain, and versions
- How do I pass GDPR consent in an OpenRTB bid request? Set regs.gdpr to 1 when the request is subject to GDPR and put the TCF consent string in user.consent.
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- GPP vs us_privacy: which should I send? Send GPP (regs.gpp plus regs.gpp_sid) where your partners support it; the US Privacy signal was deprecated by IAB Tech Lab on January 31, 2024 in favor of GPP.
- How do I signal CCPA in OpenRTB? Put the US Privacy string in regs.us_privacy, which is a first-class field in OpenRTB 2.6; on 2.5 and earlier it travels as regs.ext.us_privacy per the IAB extension.
- How do I signal COPPA in an OpenRTB request? Set regs.coppa to 1 when the request is subject to the COPPA regulations established by the US FTC, and 0 when it is not.
- What is the DSA extension in OpenRTB? The DSA transparency extension carries EU Digital Services Act ad-transparency data through OpenRTB 2.x ext blocks.
All 93 questions are listed in the OpenRTB FAQ.