Teads last month announced that is now offering 100% viewability for all CPV (cost per completed view) campaigns, and VCPM (viewable CPM) campaigns.
Teads is using Moat to measure viewabiity, and advertisers are only billed on impressions that meat the set 5 seconds viewability. Teads is auction the rest of the impressions not meeting 5 seconds as free media.
According to Teads, 100% viewability billing was introduced to move from a viewability score to a cost per viewable impression.