Advertising is a much higher margin business than retail, but the move risks drawing people away from eBay's site.
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Howard-Sarin downplayed the risk, citing how many users repeatedly return to the site. EBay's relationship with users "can survive a blip or two," he said.
"If they respond to (the mobile advertising), we're not so brittle that we think that's going to destroy their relationship with eBay," Howard-Sarin said. "They're going to come back as soon as they're done and we're not afraid of that."
EBay is working with Triad Retail Media to place the advertisements. Howard-Sarin declined to provide details of the revenue sharing agreement, saying only that eBay will get a greater portion of the revenue.