Microsoft Curate - Viewability targeting
Based on historical viewability data across several dimensions of the ad call, Microsoft Advertising has developed a methodology for determining, pre-auction, the percentage probability that an ad will be viewable to the user once it is delivered to the page, per the IAB viewability measurement standards.
You can opt to buy only impressions that have a certain percentage predicted viewability by checking the Viewability Threshold checkbox in Line Item > Targeting, and entering a percentage value.
Predicted viewability is supported for both display (banners) and video inventory on desktop and mobile web.