Malformed Advertising ID Filter
The malformed advertising ID filter is the first filter we apply when device matching. It removes all invalid advertising IDs from your dataset. You don’t need to activate or purchase this filter. It is automatically on for all clients.

An advertising ID is a string containing a fixed number of characters. Each character in the string has a given range of permitted values. If some characters are missing or appear where they shouldn’t, the ID is invalid. Because advertising IDs always follow the same format, any device with an invalid ID is fraudulent (even if that device has other valid identifiers available).

Can I see which traffic the filter rejects?

Yes. If you've purchased the Fraud Prevention Suite, you can see a tracker in your deliverables or Fraud Prevention reporting called untrusted devices::malformed advertising ID.


If you have set up global callbacks in your raw data, you can see the {activity_kind} placeholder with the value rejected_install. Add the {rejection_reason}  placeholder, which will return  Malformed advertising id.

On this topic