The rules of the exchange.
Impressions and clicks must come from real visitors to your own pages. Generating them by script, by paying people to click, or by any other artificial means is grounds for forfeiting your credit balance and closing your account.
You must hold the rights to any banner you upload and to what it links to. Banners are reviewed before they serve, but review is not legal clearance and the responsibility stays with you.
No malware, no deceptive creative, no adult content, and nothing illegal in the places it would be shown. We may reject or remove any banner, and we don't have to explain why.
Credits exist to balance the exchange. They are not money, they cannot be cashed out, and they carry no value outside vieworo.
We run this carefully but make no guarantee of uninterrupted service. If the ad server is unreachable, the snippet draws a neutral placeholder and your page keeps working.
If these terms change materially we'll say so on this page. Continuing to use the service after that means you accept the change.