European online advertising network and marketing firm AdLink Group, part of Germany’s ISP firm United Internet, has been put up for sale, possibly to a U.S.-based company, reports Frankfurter Allgemeine Zeitung, picked up by AFX. (The German language story is here). The story says UI is hoping for a triple digital millions from the sale…Adlink is valued at about 400 million Euros, while 84.3 percent is owned by United Internet.

AdLink also owns Sedo, the online marketplace for buying and selling domain names and websites; and Composite Digital, a provider of e-mail data and profiling tools.

The company has hired Morgan Stanley,  the U.S. investment bank in a deliberate attempt to find an American buyer, the story says. My guess is AOL, which has been trying to buy a European online ad operation for a while, might be a buyer. It tried to buy TradeDoubler for $900 million early last year but withdrew its bid after shareholder opposition. Then later it bought Adtech AG, an international online ad-serving company based in Frankfurt, Germany, and then earlier this year announced buying UK-based affiliate marketing network Buy.at.

• AOL Acquires Affiliate Marketing Network Buy.at
• AOL Acquires German Company Adtech AG
• AOL Withdraws $900 Million TradeDoubler Bid