Ask.com’s parent IAC is the latest to join the already crowded ad network space. The company announced that it is planning to build an in-house ad network.

The mini-network pools inventory from IAC’s collection of sites. Ads can be targeted and sold across them to reach specific audience segments.

IAC hopes to differentiate itself from other content-cum-ad-networks by enabling advertisers to sell ads against user activities. For instance, a frequent Evite or Ticketmaster user may be served ads based on parties thrown or event tickets purchased.

One analyst claims that if the ad network proves popular, it could catapult IAC into a top-tier player in online ad sales.