Brand synergy effects in multiple brand extensions

Three experiments demonstrate that the simultaneous introduction of two brand extensions can have a positive influence on their evaluations independently of parent-extension similarity. This "synergy" effect occurs when the extensions are complementary (e.g., a digital camera and a digital photo printer) but is not evident when they belong to the same category (two models of digital cameras) or to unrelated categories (a digital camera and a snowboard). In addition, the effect is restricted to extension products that are introduced by the same manufacturer. Finally, it occurs only among participants who are promotion focused and therefore are disposed to consider the benefits of owning the extensions rather than the disadvantages of doing so. These and other results suggest that the synergy effect is due to the appeal of completing a set of related products from the same manufacturer rather than the physical or functional similarity of their features to those of either the parent or each other.