US Patent 11409944 Ordinal positioning of content items based on viewport

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for adjusting ordinal positions for content item slots in response to determining that a content item slot with a highest slot ordinal position relative to the other content item slots in a resource is not within a viewport area. Adjusting the adjusting ordinal positions of either the content item slots or content items to be served in the content item slots ensures that a content item slot in the viewport displays a content item with a highest respective ordinal position in a ranking relative to other content items is rendered in the content item slot within the viewport area.