By Matt Connor · NYSE Parity and D-Quotes: How Fills Allocate
NYSE parity splits a fill across participants at the same price, so a floor broker can trade ahead of an earlier public order. See the allocation math.
NYSE parity is an allocation rule: when several participants rest at the same best price, an incoming order is dealt out among them one round lot at a time rather than filled front to back in arrival order. The participant that set the best price is paid first, up to the size it was displaying. Everything after that is shared, which is how a floor broker's electronic quote can execute ahead of a public order that has been sitting at the same price since the morning.
Most US venues do not work this way. Nasdaq and the electronic books run price-time priority, where the first order in at a price is the first order out. Parity is the third model, and it governs the continuous book of every NYSE-listed stock.
How does NYSE parity allocation work?
Three definitions carry the whole rule.
Setter priority. The order that first displays a new best bid or offer establishes the price. It is paid ahead of everyone else at that price, for a quantity capped at the size it was displaying when it set it. This is the only part of a NYSE fill that is strictly first come, first served.
A participant. Every off-floor electronic order at a given price is bundled into one participant: the book. Each floor broker holding an e-Quote at that price counts as a separate participant, and the Designated Market Maker, the firm obligated to quote the stock, is another. A price with 4,000 shares of public interest and two floor brokers on it has three participants, not hundreds.
Rounds. After setter priority is satisfied, the remainder is dealt one round lot, 100 shares, to each participant in turn, cycling until the order is filled or the price level empties. The book's allocation then passes to its individual orders by time priority.
Individual fills are small, and that ladder runs on nearly every print.
The exact SQL behind every number
SELECT
ticker,
multiIf(ticker IN ('KO', 'JPM', 'XOM', 'JNJ', 'WMT'), 'NYSE listed', 'Nasdaq listed') AS listing_venue,
round(toFloat64(sum(volume)) / sum(transactions), 0) AS avg_shares_per_trade
FROM global_markets.stocks_daily_aggs
WHERE ticker IN ('KO', 'JPM', 'XOM', 'JNJ', 'WMT', 'AAPL', 'MSFT', 'INTC', 'CSCO', 'PEP')
AND date >= today() - 120
AND date < today() - 4
GROUP BY ticker
HAVING sum(transactions) > 0
ORDER BY avg_shares_per_trade DESCAcross 10 household names over the trailing four months, the average trade printed between 50 and 119 shares. A 1,000-share order clears as many separate allocation decisions, each one running the ladder again.
A 1,000 share order, allocated round by round
The mechanics are easiest to see on a hypothetical NYSE-listed book offered at $50.00, with five pieces of interest resting there in this arrival order:
- Order A, a public limit order for 300 shares, first to display $50.00 and so the price setter.
- Order B, a public limit order for 600 shares, entered a few minutes later.
- Floor broker C, holding an e-Quote for 600 shares.
- Floor broker D, holding an e-Quote for 600 shares.
- The DMM, quoting 500 shares.
A market order to buy 1,000 shares arrives. Orders A and B are both on the book, so between them they are one participant. With the two brokers and the DMM, that is four participants at $50.00.
Setter priority pays Order A first, for the 300 shares it displayed when it set the price. That leaves 700.
The remainder goes out in rounds. Round one hands 100 shares each to the book, broker C, broker D and the DMM, leaving 300. Round two hands 100 each to the book, broker C and broker D before the incoming order runs out.
Final allocation: the book 500 shares, broker C 200, broker D 200, the DMM 100. Inside the book's 500, Order A is already full at 300, so the remaining 200 pass to Order B.
Now re-run the identical book under strict price-time. Order A fills 300, Order B fills its entire 600, and broker C takes the last 100. Broker D and the DMM get nothing.
Order B, which arrived second, receives 200 shares under parity against 600 under price-time. Broker D, which arrived fourth, receives 200 against zero. That 400-share swing is the whole of what parity does.
What price-time, pro-rata and parity each reward
Price-time priority pays in strict arrival order at each price. It rewards speed: being marginally earlier is worth the entire fill ahead of you.
Pro-rata allocation, common in futures and several options markets, splits an incoming order across resting quotes in proportion to displayed size. It rewards size.
Parity rewards presence. Size beyond the round lot needed to stay in the rotation buys no extra rounds, and arriving early buys nothing once the setter quantity is used up.
What is a D-Quote on the NYSE?
A d-Quote, short for discretionary e-Quote, is a floor broker order carrying a discretionary price range around its limit, which the broker may trade inside without a fresh instruction. Only floor brokers can enter one. These are not-held orders in character, with discretion over price and timing sitting with the broker.
The timing is the part worth knowing. MOC and LOC orders for the NYSE closing auction must be in by 3:50 p.m. ET, after which they may only be cancelled to correct a legitimate error. A d-Quote may be entered, modified or cancelled until 3:59:50 p.m. ET, ten seconds before the bell. Our guide to MOC and MOO order cutoff times lists every auction deadline. That final window sits directly in front of the largest single match of the day.
Across the same names, the 16:00 ET minute, the bar carrying the closing auction print, took between 0.6% and 3.6% of regular-session volume, with JNJ at the top of that range. Nothing else in the session concentrates that much size into one price, and our walkthrough of the NYSE closing auction covers how that single price is struck.
Broker preferencing is a different rule
Broker preferencing is a matching rule on some non-US venues, Canadian equity markets being the standard example: when one firm carries both sides at the best price, its two client orders match each other ahead of other participants there. The trigger is firm identity.
Parity applies no such test: an e-Quote earns rounds by standing at the price as a distinct participant, whoever is opposite. US equity markets do not run broker preferencing.
What parity means for a resting order
Queue position on a NYSE-listed name has two layers. One is your rank in time among the other public orders at your price. The other is the book's share of the rotation, which shrinks every time another floor broker joins that price. Neither layer is visible in the public quote: the NBBO publishes price and aggregate size, never the participant count behind them.
A fill model built on price-time will misprice NYSE-listed names in both directions, overstating fills for an early order at a busy price and understating them for interest that arrives late, the floor included.
Setter priority is the one piece of this ladder a public limit order can win outright. An order that improves the NYSE best bid or offer, rather than joining it, takes the first slice of the next order to arrive there, capped at its displayed size.
How these panels were built, and the closing print over two years
Every panel measures regular-session minutes only, 09:30 through 16:00 ET, with the 16:00 bar kept in as the closing auction print. Each trailing window ends four sessions back, clear of the ingest lag at the front edge of the tape.
The panel below tracks that print month by month for the same NYSE-listed name across the past two years.
The exact SQL behind every number
SELECT
month,
round(100 * sumIf(shares, minute_of_day = 960) / sum(shares), 1) AS closing_print_pct
FROM
(
SELECT
formatDateTime(toTimeZone(window_start, 'America/New_York'), '%Y-%m') AS month,
toFloat64(volume) AS shares,
toHour(toTimeZone(window_start, 'America/New_York')) * 60
+ toMinute(toTimeZone(window_start, 'America/New_York')) AS minute_of_day
FROM global_markets.delayed_stocks_minute_aggs
WHERE ticker = 'KO'
AND window_start >= toStartOfMonth(today() - 730)
AND window_start < today() - 4
)
WHERE minute_of_day >= 570 AND minute_of_day <= 960
GROUP BY month
HAVING sum(shares) > 0
ORDER BY monthThe share measured 2.4% in 2026-08, across 25 months of tape.
FAQ
Does a floor broker trade ahead of an earlier public order on the NYSE?
Once setter priority is satisfied, yes. A floor broker's e-Quote is its own participant in the parity rotation, while every public electronic order at that price shares a single participant slot. Arrival time ranks orders inside the book, not the split across participants.
What is a D-Quote on the NYSE?
A discretionary e-Quote, entered by a floor broker, carrying a price range the broker may trade inside without new instructions. It is eligible for the closing auction and can be entered or changed until 3:59:50 p.m. ET, ten minutes past the 3:50 p.m. ET deadline that binds MOC and LOC orders.
Is NYSE parity the same as pro-rata allocation?
No. Pro-rata splits a fill in proportion to displayed size, so a bigger quote takes a bigger slice. Parity deals round lots one at a time to each participant regardless of size, so a 200-share e-Quote and a 20,000-share book take the same amount from each round.
Does parity apply inside the closing auction?
No. Round-by-round parity governs continuous trading on the NYSE book. The closing auction is a separate single-price match with its own priority ladder, which is where the d-Quote timing window matters.
To measure the same allocation footprint on a name you follow, ask the question in plain English on the Strasmore terminal.