data are available for such a rival, the incremental price for the dominant company can be compared with the costs of the rival. Second, if no such cost data are available, it may be
possible to show that the rival was actually excluded or marginalised following the bundling by the dominant company. If such methods are used, the dominant company has the possibility to
rebut the findings by using its own incremental costs.
Incremental price of one item in bundle 192. A bundle may be discounted in various ways. In the simplest case, a bundle AB consisting of two products A and B has a separate price that is lower than the sum of the stand- alone prices of A and B. In that case the incremental price of product B is measured as the price of the bundle AB less the stand-alone price of product A. Similarly, the incremental price of a product C sold in a discounted bundle ABC is the price of ABC less the sum of the stand-alone prices of A and B (or the price of AB if such an option exists).
Multi-product Rebates 193. The calculation of the incremental price may be more complicated if the discount is given in the form of a multi-product rebate. The fact that a rebate is multi-product is not in itself problematic. A simple rebate giving a percentage discount on every purchase of a supplier’s products does not in itself tie the products together. However, competition problems may arise if the granting or the size of such a rebate is, for instance, conditional on buying several products
from the dominant company or on reaching sales targets either for several products individually or added together. In such a situation the granting or the size of a rebate for one product is dependent on the customer’s purchases of one or more other products, and the products are therefore tied in the eyes of the customer. To calculate the effect of the rebate, the incremental price should therefore incorporate the loss of rebate that the customer would incur if it stopped purchasing one but continued to purchase the other products from the dominant company. Stopping purchasing a product may mean losing the entire rebate if, for instance, the rebate was given conditional on reaching a certain target purchase of the product that the customer considers to stop purchasing. Or it may mean that the rebates granted on the remaining purchases are lower, because a certain overall target purchase level is no longer reached.