This summer's ongoing privacy debate in Washington may have scared away a handful of internet service providers that were once eager to enter the online advertising business. 

While details are still sketchy, it appears as though several ISPs, which had previously been testing NebuAd's ad-serving system, have backed out of the arena, citing tough questions from legislators over the role of cable and telephone companies in digital advertising.

Annmarie Sartor, a spokeswoman for broadband provider CenturyTel, told the Associated Press that the company was set to launch this summer, but reversed its decision after Congress raised questions about consumer privacy.

NebuAds spokeswoman Janet McGraw declined to give any specific business updates on the company or its partners amid news that many ISPs were now in the process of pulling away from the advertising business.