Millennial Media has joined forces with tech firm AppNexus to launch the Millennial Media Exchange (MMX), which the companies claim is the world’s largest premium mobile advertising exchange. They say the MMX provides advertisers and developers with “a unique opportunity to buy and sell on a real-time, programmatic basis with unique data at scale.”

AppNexus has been around since 2007. It started out in the desktop space but has been focused on mobile for the past couple of years. It’s a tech platform that is used by many ad networks to add additional tracking, targeting, analytics and campaign optimisation capabilities to their own platform.

Today’s deal combines the programmatic selling of mobile inventory across the MMX, with Millennial Media’s proposed acquisition of Jumptap, which is one of the largest programmatic buyers of mobile exchange-based impressions.

“By adding the industry-leading technology of AppNexus to the existing RTB exchange foundation that we have already built and acquired, the MMX will leapfrog existing solutions in the market and unlock tremendous value for our partners,” said Millennial Media chairman and CEO, Paul Palmieri. “Our full ad tech stack will be one of the most powerful in the digital advertising industry, with further innovations already under development.”

For AppNexus, CEO Brian O’Kelley said: “In April, we made a commitment to solve the challenges that have kept mobile from reaching its full potential. When a large, premium advertising company and a leading technology provider come together, it accelerates the market into rapid expansion. Our partnership with Millennial Media will unlock their scale, high quality supply and unique data to ignite the mobile marketplace.”

The companies say the partnership will significantly enhance reach and performance for advertisers, while for publishers and developers, it will yield superior results, greater control, and improved monetization opportunities.

The MMX is available immediately to a select group of advertisers who have already established MMX seats.