Competitive Poaching in Search Advertising: Two Randomized Field Experiments

Keyword searches with brand names occur very commonly on search engines, enabling firms to infer not only when consumers are searching for them but also when consumers are searching for their competitors. This enables firms to generate traffic from search advertising by bidding not only on their own keywords but also on competitors’ keywords. The strategy of bidding on competitors’ keywords, known as competitive poaching, presents unique opportunities for academic research. In this research, we examine the factors that influence the effectiveness of competitive poaching, specifically the role of different ad copies and the type of competitor (poached brand) from which a brand is poaching. We also examine how the presence of sponsored ads from the poached brand affects competitive poaching. We collected data from two randomized field experiments, one with a business school in the Northeastern United States and the other one with a leading automobile dealership company, where these firms bid on keywords of competing brands and randomly display different types of ad copies in the sponsored search listings. We find that, when poaching on keywords of high-quality brands, ad copies that feature vertical differentiation are more effective than the control ad copies, which do not convey any differentiation or prescriptive messages. We also find that when poaching from low-quality brands, ad copies featuring horizontal differentiation perform better than the control ad copies. Finally, we show that the presence of the poached brand’s own ad has a positive association with the ad effectiveness of the poaching brand when that poached brand is high quality and a negative association when the poached brand is low quality. The academic and managerial contributions are also discussed.