• by Tyler Loechner  @mp_tyler, December 1, 2014

Since being founded in 2007, ad tech firm AppNexus has become one of the major players in the programmatic advertising space. Yet operationally, it’s a similar company to the one it was seven years ago.

Now AppNexus is mixing things up internally to keep pace with the evolving programmatic ad industry.

The company on Monday announced the formation of four new business units. The four units will focus on publishers, programmatic media companies, agencies and advertisers, and marketplaces, respectively. Michael Rubenstein, president of AppNexus, told Real-Time Daily that the transformation has been in the works for about a year.

AppNexus has operated as a single business line company that licenses programmatic ad tech to companies for years, but as the programmatic industry expanded, AppNexus spread with it. The company has grown, too, and will end 2014 with close to 800 employees after entering the year with 525.

“We’re creating companies within the company, essentially,” said Rubenstein.

AppNexus has promoted Ryan Christensen to GM of publishers, where he will oversee the new publishers unit. He was previously SVP of product at AppNexus. He will also oversee the company’s use of OAS, the ad server AppNexus recently acquired.

Casey Birtwell has been promoted to GM of programmatic media companies and will head that new division. He was previously SVP of strategy and operations at AppNexus.

Andy Atherton will serve as GM of marketplaces. He was previously SVP of discovery at AppNexus and oversaw the company’s development and launch of Twixt, a programmatic direct solution.

AppNexus has not yet named a GM of its new agencies and advertisers unit.

There will still be corporate level operations at AppNexus, and the company has done some reshuffling there as well. Brandon Atkinson has been named chief people officer of AppNexus, a new role at the company. He was previously SVP of global services of AppNexus. In addition, Catherine Williams has been named chief data scientist, also a new role at the company.

Atkinson and Williams will be responsible for keeping AppNexus operating as one unit -- both from a people and data perspective -- despite the split into four categories. The company wanted data and people to be a horizontal function across all units, Rubenstein explained.

Geir Magnusson, who had been promoted to CTO of AppNexus earlier this year, will be leaving the company, as each of the four new units will have its own CTO-level or equivalent employee, Rubenstein noted.

Rubenstein said the internal transformation is already underway, with most of the reorganization expected to be in place by the end of the year. The plans were announced internally last week.