Rubicon Project

Was one of the largest independent SSPs globally before merging to form Magnite; its technology now underpins Magnite DV+

Rubicon Project was one of the most influential sell-side platforms (SSP) in the history of programmatic advertising. Founded in 2007 and headquartered in Los Angeles, California, the company built one of the largest independent marketplaces connecting digital publishers with advertisers and demand-side platforms (DSPs). Its technology automated the buying and selling of digital advertising inventory at scale, enabling publishers to maximize yield across display, mobile, video, and audio formats. At its peak, Rubicon Project processed billions of ad transactions daily and was a central infrastructure provider for the open programmatic ecosystem. Rubicon Project went public on the New York Stock Exchange in 2014 under the ticker RUBI, signaling its prominence in the rapidly maturing programmatic advertising industry. The company championed header bidding adoption, launched its own header bidding wrapper (Prebid.js contributions), and was a vocal advocate for supply chain transparency through initiatives like ads.txt and sellers.json. Despite facing revenue headwinds from industry consolidation and the rise of walled gardens, Rubicon Project remained a key independent player for publishers seeking alternatives to Google's ad stack. On April 1, 2020, Rubicon Project completed a merger of equals with Telaria, a leading CTV (connected television) SSP, to form Magnite — the largest independent omnichannel SSP in the world. Both the Rubicon Project and Telaria brand names were retired as part of the transaction. Rubicon Project's core technology and publisher relationships became the foundation of Magnite's DV+ business unit, which handles display, digital video, audio, and non-CTV inventory, while Telaria's technology underpins Magnite's CTV offering.

• 2007Founded
• 2020Rebranded to Magnite