NebuAd, the online ad targeter, shut down on Friday, following legal troubles, paidContent reported.

After a suit was filed against the company by consumers accusing NebuAd of privacy violations, the ad targeter cut down its staff and struggled to find ISP providers that were willing to test the targeted ads on their clients, amid growing controversy associated with the company.

While targeted ads remain an area of interest for online service providers, they are heavily watched by lawmakers and critics, making this form of advertising a potentially dangerous one to enter into, according to paidContent.

"Consumer advocates said that NebuAd's Internet service provider-based platform presented a far more significant privacy threat than older forms of targeting because broadband companies have access to users' entire Web histories -- including search queries and activity at non-commercial sites. Older behavioral targeting companies only track users at a limited number of sites within a network," a MediaPost article reported Monday.