Short answer: MMPs mostly give an install to the last qualifying click, and clicks beat views. If a user touched two campaigns, the later click wins. When the winner looks plainly wrong, check the tracking link's campaign parameters next.
How an MMP picks the winning campaign
Last-touch attribution: a model that gives full credit for an install to the final qualifying touchpoint before it, ignoring earlier ones.
TikTok's help centre describes MMPs as mostly using last-click attribution and de-duplicating across networks. Apple's AdAttributionKit follows a similar order: click-through always beats view-through, then the most recent wins.
Is the attribution actually wrong?
Often it is not. If the user clicked a second campaign after the first, last click gives the second the install, which is what the model is designed to do. It is wrong only if the touchpoints themselves are mislabelled or fall outside their windows.
Likely causes
- A later click on another campaign or network. Last click gives the install to the later click (general practice for MMPs).
- A click beat a view. A view on your intended campaign loses to any click elsewhere.
- Wrong parameters in the tracking link. A copied link still carries an old campaign name or ID (general practice).
- Windows differ by network. A long window on one network keeps old clicks eligible while a short window on another drops recent ones. See the attribution windows guide.
- Referrer not decoded. On Android, Meta's campaign data sits encrypted in the Play referrer's utm_content field; without the key, the MMP cannot read it.
How to confirm it
- Look up a sample of the affected installs in your MMP and list every touchpoint with its timestamp.
- Check whether a later click on another campaign exists.
- Open the tracking link and read its campaign parameters.
- Compare each network's lookback window in your MMP.
- For Meta on Android, confirm the Install Referrer decryption key is set in your MMP.
How to fix it
- Correct the campaign parameters in the tracking link and replace old copies.
- Use one naming convention for campaigns across networks.
- Review window lengths so each network is judged on comparable terms.
- Add the Meta Install Referrer decryption key if it is missing.
- Accept that last click will move credit between campaigns that share users.
| What you see | Likely reason |
|---|---|
| Later click on another network | Last-click deduplication |
| Only a view on the expected campaign | Click beat view |
| Wrong campaign name on every install | Link parameters |
| Meta Android installs unlabelled | Referrer not decrypted |
The organic installs troubleshooter covers installs that lose their source entirely, and installs claimed by two networks covers overlap between networks.