Ten leading online ad networks have this week launched a UK ad exchange in partnership with US company AdECN, with high hopes of revolutionising the buying and selling of inventory.

The launch, while it was still impending, has been covered in this news blog before and it is significant news for the online industry that this has now got off the ground.

The AdECN (UK) Consortium, which has been set up as a not-for-profit entity, will allow its members “to buy and sell ad inventory for their advertiser and publisher clients on an automated and neutral exchange“.

It offers advertisers a transparent environment to buy space, and cut down on the time spent filling out orders.

Venture-backed AdECN’s CEO and founder Bill Urschel has succeeded in getting the message through that the industry, with its old-fashioned reliance on faxes and telephones, has been years behind the financial markets in instituting automated exchanges.

He has also done well to get rival networks together in what has become an increasingly competitive space. Liquidity in the market will ultimately benefit everyone.

The key to the AdECN exchange is its neutrality,” said John Cole, managing director of MediaRun, one of the consortium’s members.

Cole, a driving force behind the UK consortium, added: “This is the first time that we will have the opportunity to buy and sell display advertising in an efficient way. The present system is nowhere near efficient enough and attracts all sorts of middlemen. The closer an advertiser can get to the source, the better the results; this is the perfect system for eliminating chain-buying.”

The news is a further boost to online ad networks which now account for up to 25% of UK display advertising spend.

The 40-plus online ad networks operating in the UK made an estimated £120 million in revenue during 2006, according to E-consultancy’s 2007 Online Advertising Networks Buyer’s Guide which contains profiles of the leading networks in this space.