Competitive bidding
Same-listing bid chains, genuine competitor transitions and what they can—and cannot—tell us.
Bids through Oct 18, 2026America/Toronto reporting cutoffOct 17 excludedSame-listing sequences
Consecutive bids on one listing do not mean a bidder owns the item. This dataset contains no consignor or seller identifiers.
| Transition type | Total pairs | Within 3 sec | Within 5 sec |
|---|---|---|---|
| Same account bids consecutively | 128 | 72 | 73 |
| Different accounts bid consecutively | 17,105 | 3 | 5 |
Pairs are derived from the complete observed history through the cutoff; ties at one-second precision can make exact within-second ordering uncertain.
Accounts with repeated same-listing sequences
| Account | Rapid consecutive same-listing pairs ≤3 sec |
|---|---|
| connectedbysound | 30 |
| scottpeter | 18 |
| mrss2006 | 9 |
| kimbloxam | 5 |
| emiliejones | 5 |
| jamaicajamaica | 4 |
| navu0001 | 1 |
Repeated bids may involve proxy-bidding or platform bidding increments. Bid-history entries alone do not establish the underlying click sequence or intention.
Competitive counterbidding and interpretation
Near-instant replies by different accounts on the same listing are rare in this sample. This weakens a claim that the observed high-frequency group is systematically responding immediately to competing bids. Rapid cross-listing activity is a separate pattern.
To test price pressure after closure, capture final prices and verified winning bidders. Merely noting that an account is currently outbid does not prove it intentionally increased a price.
October 19 data refresh
Consecutive same-listing bids by the same account are distinct from bids by competing accounts. Neither pattern establishes seller involvement or improper behaviour.
Full dataset export: completed-day bids · October 19 catalogue snapshot · coverage and limitations.