Confirmed: resellers arbitrage your geo caps against the source's geo caps
You cap a campaign at 50k US impressions. The reseller in the middle doesn't — they keep buying US from the source past your cap and dump the overflow into a different buyer or a smartlink, pocketing the spread.
The tell: source-side reporting shows more US volume than your tracker recorded, with the gap unaccounted. If you can't reconcile source impressions to tracker impressions within ~5%, there's a hand in the middle.
— confidence: high
Pop Wire
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