An approach is provided for associating structured information as feature-value pairs with advertisements at an advertisement system that provides advertisements for presentation with primary content. Feature-value pairs corresponding with advertisements describe features of the products or services associated with the advertisements. The feature-value pairs may be used by the advertisement system in a number of different manners, including, among other things: using the feature-value pairs during selection of advertisements for presentation with primary content: allowing users to sort and/or filter advertisements during presentation with primary content based on the associated feature-value pairs; exposing additional information with the advertisements; facilitating fraud detection for the advertisement system; and enabling a hybrid pricing model.