Magnite, Inc.

Magnite, Inc. (NASDAQ: MGNI) is the largest independent sell-side advertising platform on the open web and the largest independent CTV SSP. The current company is the product of four years of structural M&A: the April 2020 Rubicon Project–Telaria merger that created Magnite, the April 2021 acquisition of SpotX from RTL Group ($1.17B), and the July 2021 acquisition of SpringServe ($31M cash plus stock). The combined entity reports across two operating segments — Magnite Streaming (the CTV SSP plus the SpringServe ad server) and Magnite DV+ (web and mobile display and video).

The May 6, 2026 print is the structural inflection. Management’s own Q1 guidance, issued Feb. 25 and reaffirmed on April 20, puts CTV contribution ex-TAC above 50 percent of the segment total at every corner of the range — the first quarter Magnite would be definitionally a CTV-first business. The April 20 release packaged that guidance reaffirmation with the announcement that CFO David Day will retire effective Sept. 30, 2026 and continue as a special advisor through May 31, 2027.

Surrounding the print: the SpringServe next-generation release (April 2025) consolidated the streaming SSP and ad server into a single client surface for Disney Advertising, LG Ad Solutions, Paramount, Roku, Samsung, and Warner Bros. Discovery; AMC Networks routed unified linear and streaming inventory through ClearLine on April 15, 2026; and on April 21, Magnite took a founding seat on the IAB Tech Lab Programmatic Governance Council alongside The Trade Desk, PubMatic, Amazon Ads, Disney, and the major holding-company agencies.

For full editorial coverage, see The State of Streaming’s Magnite Q1 2026 preview (April 25, 2026) and the IAB Tech Lab PGC launch analysis (April 26, 2026).