As part of Yahoo's strategy to remake the Right Media Exchange into a high-quality ad marketplace, the unit is shutting down its ad platform aimed at smaller Web publishers. The Direct Market Exchange (DMX) will stop serving ads Jan. 31 2010, although users will be able to access reports until March 1.

"Right Media and Yahoo! have made a strategic decision to focus our business on becoming a premium and differentiated exchange marketplace. As such, the executive team made the difficult decision to discontinue supporting DMX," stated Yahoo in a FAQ about the move on the Right Media site.

It also explained that ad networks participating in DMX, including Adtegrity, Bannerconnect, and CPX Interactive, and .Fox Networks, would be asked to settle all payment obligations through Jan. 31.

The move follows steps begun last month by Yahoo to reposition Right Media as an exchange focused on premium, targeted inventory rather than being known as a trading hub for scores of anonymous ad networks.

Since the overhaul was announced in mid-November, Right Media founder Michael Walrath has left Yahoo, where he most recently served as senior vice president of advertising strategy. The Web portal acquired Right Media in 2007 for $680 million in cash and stock.

For its part, CPX Interactive said it plans to work directly with small and mid-sized publishers it has worked with through DMX. David Shay, executive vice president for marketing at CPX, added that there is a misperception that most of the company's business comes from plugging into ad exchanges rather than its own network. "We have always kept our own stable of direct publishers and advertisers," he said. "We don't see a huge change to us or the ad ecosystem."

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