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A comment on eBay Explicitly Bans AI "Buy for Me" Agents in User Agreement Update. Parent comment

Re:eBay Explicitly Bans AI "Buy for Me" Agents in User Agree... by pwg on Wednesday January 21, 2026 @06:09PM (#46712977)
From what I've seen discussed, it seems some percentage of "sniping" is to attempt to obtain both "winning bid" and "lowest possible price" (note, not the same as "max willing to pay for the same item"). The sniper is trying to hide interest, so as not to attract other interested bidders, and therefore grab "a great deal" of a small increment above the starting bid price.

And this probably appears to work enough times in the snipers favor to trick them into thinking it is a winning strategy, whereas they likely would have won the same auctions in the end by just bidding that 'minimum' as their maximum bid. But as they can't easily (i.e., without expense) A/B test their strategy, they get no feedback that sniping isn't really helping them like they think it is helping them.

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Re:eBay Explicitly Bans AI "Buy for Me" Agents in User Agree... by cge on Thursday January 22, 2026 @04:38AM (#46717058)
> But as they can't easily (i.e., without expense) A/B test their strategy

There also isn't really any detriment. At worst, the sniper is making the same bid they would have made otherwise. If the opposing bidders are not purely rational, and have not put in their actual maximum bid, then sniping can deprive them of that opportunity and thus lowers the hammer price.

And bidders are not purely rational, especially when the items are not purely utilitarian. Getting notifications that you have been outbid has an emotional effect, as does having time to think about raising the bid.

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Re:eBay Explicitly Bans AI "Buy for Me" Agents in User Agree... by duskdozer on Thursday January 22, 2026 @05:58AM (#46717622)
they notify the bidder when they're outbid, and the incremental price increases can make it tempting for someone to adjust their idea of their max price. sniping deprives them of that opportunity.
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