Google’s ad system is a reliable source of income because both the ad-making partner and ad-receiving individual are both customers of Google’s. So as long as Google maintains its market dominance with the search product, supplier bargaining power will remain low. Google’s cost of revenue as a percentage of sales in 2007 was 40% (Google, 2007). This number is the same for Yahoo (Google, 2007) suggesting that both companies are equally efficient at maintaining supplier-seller collaboration.