What is the difference between device.lmt and device.dnt?
Answer
device.dnt is the browser Do Not Track header flag, while device.lmt is the OS-level Limit Ad Tracking signal from mobile platforms such as iOS and Android. For both, 0 means tracking is unrestricted and 1 means tracking must be limited. When lmt=1, buyers must limit tracking per the platform's commercial guidelines: no profiling or retargeting off the device ID, and the ifa is typically absent or zeroed anyway. dnt matters for web inventory, lmt for app inventory; requests should not carry a device identifier usage that contradicts either flag.
Fields in this answer
| Field | Type | Since | Status in 2.6 |
|---|---|---|---|
device.dnt | integer | 2.0 | Current |
device.lmt | integer | 2.3 | Current |
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