An Upweight in online advertising is a term to do with optimising ad campaigns. It means when a placement is performing well, that further impressions are moved to that placement to improve the overall performance of a campaign. Creating an upweight would usually involve making a new ad line that is only targeted at successful placements.
Glossary IndexDefinition: Upweight
in Conversion Rate Optimisation / Display Advertising / Paid Search / Social Media Advertising by Justin Driskill (updated on )