Competitive Poaching in Search Advertising: Two Randomized Field Experiments

Keyword searches with brand names enable 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 practitioners. This study examines factors that influence the effectiveness of 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 through quality signals are more effective than the control ad copies that do not convey any differentiation or prescriptive messages. We also find that when poaching from low-quality brands, ad copies featuring horizontal differentiation through nonquality attributes perform better than the control ad copies. Finally, 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.