Lot & Hammer

The dataset

Every lot, not the interesting ones.

1,534 lots. Two houses. Every lot in thirteen Sotheby's sales, plus three years of Heritage game-used results. Here's what's in it, where it thins out, and which findings have survived contact with the full population.

What's in it

Two houses, captured differently because they publish differently. Sotheby's sells in discrete themed sales, so it's captured sale by sale. Heritage runs a searchable archive across years, so it's captured by year and sport. Where a sale is held as a summary rather than lot by lot, it says so, and it doesn't get used for anything population-level.

Sotheby's — thirteen sales, Dec 2025 to Jul 2026

SaleClosedLotsCaptureEstimates
NBA Auctions Premier — ChristmasDec 202552Lot by lot
The Scottie Pippen Collection10 Mar 202671Lot by lot
NBA Auctions Premier — All-Star16 Mar 202653Lot by lot
NBA Auctions Weekly — All-Star30 Mar 202694Lot by lot
The Stephen Curry Collection28 Apr 202681Lot by lot81 lots
Moments of Impact — mixed weekly18 May 2026115Lot by lot
NBA Auctions Premier — Rookie Collection15 Jun 202689Lot by lot
NBA Auctions Premier — Finals8 Jul 202635Lot by lot
NBA Finals, Part Two13 Jul 202615Lot by lot
The Beautiful Game16 Jul 202658Lot by lot54 lots
NBA Finals, Part Three20 Jul 202660Lot by lot
Summer Sports Marquee20 Jul 2026171Lot by lot165 lots
NBA Auctions Weekly — Christmas in July27 Jul 202661Lot by lot
Thirteen sales955955 lot by lot300 lots
Captured from Sotheby's published results pages. All thirteen sales are held lot by lot, and in every one the row count matches the house's own lot count exactly. No summaries remain. Calls are made at five houses; this dataset is Sotheby's only, and no finding here is claimed to generalise beyond it.

Heritage — game-used, Signature auctions

SetAuctionsLotsMedianTop lot
Basketball 2024Five — full year183$4,200$504,000
Basketball 2025Five — full year194$3,477$2,623,000
Basketball 2026Two — part year73$2,928$176,900
Football 2026Two — part year129$1,708$106,750
Heritage579
Prices are all-in, as Heritage publishes them. The premium is derived rather than assumed: testing which divisor puts hammer prices on round numbers gives 20% for 2024 and 22% from 2025, fitting 94% and 87% of lots respectively. Heritage publishes floors rather than ranges, and the archive doesn't show them, so nothing here can score estimate accuracy.

The most important boundary on this page. Of 1,534 lots, only 300 carry a published estimate — all of them at Sotheby's. Heritage adds population and comparables and cannot test the house's accuracy at all. Three sales published estimates, carrying 300 lots between them — but they don't pool, and it would be convenient to pretend otherwise. Two are ordinary consigned sales: 219 lots, 63.5% below the low estimate, median 0.75×. The third is a single-owner sale direct from the athlete, and it runs the other way entirely. Averaging them would produce a number describing no market that exists.

How a sale gets captured

One rule, and it exists because breaking it has cost me a published finding.

Capture the full results page before analysing anything. Not the lots I called — every lot. Then check the lot count on the page against the count in the file. If the page says sixty-one and the file holds thirty-one, I don't have the sale, and nothing gets calculated until I do.

That sounds too obvious to need writing down. It isn't what I was doing. I built an argument about a house's ceiling on seventy-three lots drawn from two auctions in a part-year that happened to exclude the biggest sale of the period, and I'd turned down an offer of the missing data on the grounds that I had enough. Eight live calls were resting on it before I caught it.

Every error in this project traces to the same thing: analysing the data on hand instead of establishing what data exists. So the capture rule sits at the front of the file, above the findings, where it interrupts.

What has replicated

Findings that survive the full population, with the sample each one rests on. Anything that held in one sale and failed in another is in the next section, not this one.

FindingEffectBase
Lots close below the low estimate63.5%219 lots, the two sales with estimates
Catalogue position — premier sale vs weeklyup to 14.6×Confirmed three ways, three separate events
Championship team over losing team4.55×10 bench jerseys, one game, one sale
Worn over issued1.75×58 role-player lots, full population
Name effect, product held identical21.2×30 coach lots, identical product, same sale
Access sale beats estimate75.3%81 lots, full population, one access sale
Access premium, on resale−31%One shoe, two sales, ten weeks apart
Garment hierarchy — jersey over warm-up topSame team, same series, same sale
Photo match at Heritage5.28×450 lots, replicated in three separate years

Two of these are worth reading in the opposite direction to how they sound. The worn-over-issued ratio looks far larger in raw form — one sale reads at 10× — but that gap is player tier, not provenance: starters get the worn items and bench players get the issued ones. Anyone quoting much above 2× is measuring who wore it.

The name effect is the cleanest of these, because the product is held constant. Thirty NBA head coaches, the same custom Air Max 90, the same charity, the same sale, all sold within a week of each other. Median $1,024. Steve Kerr's pair made $21,760 — twenty-one times the median and 5.7 times the next coach. Nothing about the object differs. The only variable is whose feet were in it.

One refinement the partial capture couldn't see: the series is thirty-three lots, not thirty. Three are broadcast-crew pairs rather than coaches, and one of them — the NBC crew — outsold every coach except Kerr. Counted that way Kerr is 5.3 times the next lot rather than 5.7 times the next coach. Both are true of different populations, which is why the population gets named.

The photo-match number is the one I'd trust most, because it's the only finding here that has been tested three times against independent populations. Heritage basketball runs 6.78× in 2024, 3.62× in 2025 and 5.61× in 2026 — separate years, separate consignments, same direction every time. I published the 5.61× first, from 2026 alone. Three years later it turns out to sit inside the range rather than being the range, which is roughly the best outcome a single-year number can hope for.

And the garment hierarchy is relative, not absolute. Shorts sat at the bottom of one Finals sale and took the top four slots in an All-Star weekly, because the jerseys had been held back for the premier sale. What a category is worth depends on what else is in the room.

The sale that runs backwards

Every finding above about estimates comes from ordinary consigned sales, where the house is guessing at what someone will pay for an object it was handed. One sale in the dataset isn't that. It was single-owner, direct from the athlete, sold once, for a foundation — and it inverts the result completely.

61 of its 81 lots closed at or above the low estimate. Median 1.50×. In the two consigned sales, 63.5% closed below. Same house, same premium, same season, opposite direction.

The top lot is the cleanest illustration of what's being paid for. A warm-up-worn pair carrying a $3,000–5,000 estimate closed at $76,800 — twenty times the low. Its only real distinguishing feature was that it was worn on the first night of the run everybody was following.

And the premium doesn't travel. A game-worn, dual-signed, inscribed pair from that sale closed at $70,400 in April. The same shoe resold at a different house ten weeks later for $48,800. Down 31%, with nothing about the object changed. What changed is that you could no longer say you bought it from him.

Two access sales in the dataset now, and they're consistent with each other. That's an observation with a sample of two, which is why it's described here rather than stated as a law.

What isn't published, and why

Held back — failed replication

Counting milestones. In the Marquee this was the finding of the month: nine lots, median 0.54× low estimate, only 11% beating it — a 10,000th point, a 1,000th game, a 20,000th point, a first career home run. Then the same test in the soccer sale ran the other way, milestone lots beating no-moment lots. Opposite direction, and the counter-sample is three lots. One sale is an observation, not a law.

Retracted — published, then withdrawn

“The Heritage ceiling is $176,900.” Built on 73 lots drawn from two auctions in a part year — Heritage runs about five a year, and the sample happened to miss the big ones. The full three-year population has a photo-matched Michael Jordan uniform at $2,623,000. Fourteen times the number I called a ceiling. Nothing about the reasoning was wrong; the sample was.

“Four of four six-figure vintage jerseys closed below low estimate.” Built from truncated lot titles. One was a warm-up jacket rather than a jersey. One was an apparent match, not a conclusive one. The LeBron carried a genuine milestone that the truncated title hid. And a 1960 Rome Olympic jersey belonged in the sample and was never looked for. The full retraction.

Worn beats issued 2.00× became 1.75× once the population went from a 26-lot subset to all 58. Correction here.

Open — not published either way

An All-Star debut warm-up set took top lot of its sale at $76,800, beating a much bigger name's set by 5.5×. On its face that contradicts the name effect. Either the All-Star debut premium is extraordinary, or there's a collector base the lot title doesn't show. It stays out of the research until one of those is established.

The floor under all of it

Two lots in the same sale, described word for word identically — same player, same product, same series. One closed at $512. The other at $2,560.

Five times apart, for objects nobody could tell apart. That's not a pricing insight, it's the noise floor, and no forecasting method beats it. Some part of every miss on this site is simply which minute a lot happened to close in. It gets stated in every report for the same reason the sample sizes do.

What gets captured next

The estimate-accuracy finding is the strongest thing in the dataset and it still rests on two consigned sales. So the priority is sales that publish estimates — marquee and themed sales, Heritage floors, Grey Flannel — rather than more volume from weekly league-consigned sales, which add jerseys but no number to be scored against.

Every Sotheby's sale in the dataset is now captured lot by lot, so the next gains come from breadth rather than depth. Heritage 2026 is still a part year — two auctions of about five, and the one missing is the August sale this site has twenty-six live calls on. So no 2026 Heritage trend gets computed until it closes. Football now has a 129-lot base where it previously had none. Baseball is deprioritised.

For how a call is scored against all this — what counts as a hit, how premiums are converted, and what a no-skill rule achieves on the same lots — that's the methodology page.