• by Joe Mandese  @mp_joemandese, September 30, 2011

Advertisers and agencies now use ad networks, exchanges and/or DSPs (demand-side platforms) to buy more than half their online display advertising, according to findings of an Econsultancy survey of advertisers and agencies released this morning by the Rubicon Project.

Breaking that stat down, the respondents said they bought:

• 55% of their display inventory through ad networks • 32% through DSPs • 30% through exchanges

The role of DSPs is much greater in North American than Europe, where half of all online display ad buys are now made through one of the myriad of platforms now servicing the online display advertising marketplace, vs. only 27% in Europe.

The study also found that almost half (46%) of online display advertising media plans now include ad networks, up from 32% in 2009.