Sniping is the practice of placing a winning bid in the final seconds of an online auction to prevent the previous high bidder from responding before the close. Auction software can be set up by bidders to snipe automatically — entering a bid 5 seconds before close, for example.
Sniping is controversial but generally legal. It exploits the timing structure of fixed-close online auctions: a bidder with a higher maximum doesn’t always win if their proxy bid wasn’t fully exercised before the snipe lands. Soft-close auctions (which auto-extend the close time when late bids arrive) eliminate sniping advantages. Most modern platforms default to soft close to keep bidding fair.
Third-party sniping services (BidNapper, Gixen, others) emerged in the early 2000s to automate the practice for eBay buyers. Some of these services are still operational, though their value has declined as platforms migrated to soft-close auction structures. Sniping is at its most effective on platforms with hard close times and weak proxy systems — conditions that have been actively engineered out of most modern online auctions.