5. The method of claim 4 , comprising, before receiving the intrusion score: identifying a sponsor account associated with the sponsored content item, the sponsor account being associated with an additional sponsored content item; and based on the previous determination, precluding serving the additional sponsored content item.
4. The method of claim 1 , comprising: before receiving the intrusion score, and based on a previous determination by the intrusion detection engine, precluding serving of the sponsored content item associated with the landing page.