MGNI ▼ -0.6% - Magnite, Inc. $MGNI - Magnite Named Primary Video Ad Server and a Programmatic Technology Provider for HP TV+ Magnite fell 0.6% despite being named as the primary video ad server and programmatic technology provider for HP TV+, a partnership that expands its reach into connected TV advertising for HP's streaming service. 23-SEP-2026 08:00 AM ET