The challenge
Redbrain is an e-commerce performance partner that specializes in driving incremental sales for retailers. As competition in the Shopping Ads space intensified, its client eBay faced increasing pressure to cost-effectively maintain visibility and attract new customers. Aggressive auction activity from emerging competitors made it increasingly difficult to maintain a strong presence across competitive markets.
eBay needed a more agile strategy to help scale reach, reactivate dormant users
and bring in new customers. Particular focus was placed on promoting affordable products that would drive first-time purchases and long-term value.
The approach
Redbrain used its proprietary AI and performance data to support optimized campaign design and reach new customer segments.
It successfully layered this with Google return on ad spend (ROAS) Smart Bidding and a multi-seller Merchant Center setup, maximizing exposure, efficiency, and control. Redbrain worked with eBay to validate campaign performance through ongoing incrementality testing, ensuring net-new growth and minimizing existing overlap.
The results
The collaboration delivered strong, measurable outcomes. In Q1 2025 alone, eBay saw a 62% sales value growth in the UK and 84% in Germany year on year. These gains were directly linked to the lower- priced product strategy, improved campaign segmentation, and expanded CSS coverage.
Incrementality testing confirmed Redbrain’s contribution was not only effective but drove net-new revenue
validating the success of its model and laying the foundation for future expansion.
