Is off-exchange or short volume the same as dark pool volume?
By Faizan Ahmad. Updated .
No, they're three different numbers. Off-exchange volume is every stock trade reported to FINRA instead of executed on an exchange: dark pools (ATSs), plus wholesalers and other brokers trading from their own books, so dark pool volume is only one slice of it. FINRA's daily short sale volume is the part of that off-exchange volume marked as short sales. It isn't short interest, it leaves out exchange trades, and FINRA itself explains why it can make shorting look heavier than it is.
Off-exchange, dark pool, short volume, short interest: what each one counts
| Number | What it counts | Where and when it's published | Common mistake |
|---|---|---|---|
| Off-exchange volume | Every trade reported to a FINRA facility rather than done on an exchange | Trade by trade on the consolidated tape, reported within 10 seconds (big negotiated trades often later) | Calling all of it "dark pool" |
| Dark pool (ATS) volume | Trades executed inside alternative trading systems | FINRA, weekly for each ATS in each stock, two weeks later for Tier 1 stocks and four weeks for the rest | Assuming it includes wholesalers' retail fills |
| Short sale volume | Off-exchange trades marked as short sales, per stock per day | FINRA daily files, posted by 6:00 PM ET on the trade date | Reading it as bets against the stock |
| Short interest | Short positions still open on a set date | Reported twice a month | Comparing it directly with daily short volume |
Why is off-exchange volume bigger than dark pool volume?
Because much of it isn't a dark pool at all. The SEC said in 2022 that retail brokers route more than 90% of individual investors' marketable stock orders to wholesalers, which typically fill them internally. Those fills are off-exchange, reported to the same FINRA facilities, and counted in the same totals as true dark pool trades. FINRA keeps the two apart in its own transparency data: ATS volume on one side, volume executed by firms outside an ATS on the other. How much trading happens in dark pools gives the split.
Data tools blur it. Tradytics labels every print reported to a FINRA trade reporting facility "Dark pool." Strictly, that label covers wholesaler and other dealer trades too, not only ATSs. It's still the right data for finding where big size traded, which is what a print feed is for.
Why does FINRA short volume look so high?
FINRA published an explainer on reading these files in May 2019. It gives two reasons, and a third comes from the definition itself:
- It leaves out exchanges. The files cover trades reported to FINRA's facilities only, and FINRA says they aren't consolidated with exchange data. Its worked example: a stock shows 3,000 short shares out of 15,000 on FINRA's files, which looks like 20%. Add the 125,000 shares that traded on the NYSE that day and the combined short share falls to 10.7%.
- It misses offsetting buys. When a firm fills a customer's order to sell, it may first sell the same number of shares from its own account to another firm, then buy the customer's shares. FINRA publishes only the trade between the two firms, so the short sale is counted and the matching purchase isn't.
- It's volume, not positions. A short sold at 10:00 AM and bought back at 2:00 PM adds to short volume but leaves no short interest. FINRA says outright that its daily files aren't meant to equal short interest, which measures positions held on two dates each month.
So what is "dark pool short volume"?
Usually it's FINRA's off-exchange short sale volume under another name. It isn't limited to dark pools, it includes wholesaler and dealer trades, and it carries all three distortions above. A high percentage on its own says little about whether anyone is betting against the stock. If you want to know how much stock is sold short, short interest is the better measure.
What is dark pool data actually good for?
Where big size changed hands, and at what price. On October 30, 2026, QQQ closed at $692.74, just above a dark pool level at $690.36 ($3.53B in 31 off-exchange prints over the last 10 sessions), with a much bigger one overhead at $715.20 ($11.31B in 152 prints). QQQ sees about $5.67B of dark pool and block prints on a usual day, so that upper level holds roughly two usual days of size. That's a statement about price and size. Short volume can't tell you that, and dark pool levels can't tell you who is short. Read each for what it measures; what dark pool levels are and how to read dark pool prints cover the dark pool side.
How to see it on Tradytics
A stock's dark pool page, like QQQ's, shows prints today, the 10-session dark pool levels, and how much traded today against a usual day. The market-wide dark pool page lists the prints with their venue. On Live and Pro, prints appear within about 15 minutes of their report; Free shows yesterday's session.
Common questions
Is high short volume bearish?
Not by itself. FINRA's files leave out exchange trades and the purchases that offset facilitation short sales, so the ratio overstates shorting. Short interest is the better gauge of bets against a stock.
Where can I download FINRA's short sale volume?
On FINRA's short sale volume data page: daily files for each trade reporting facility plus a consolidated file, posted by 6:00 PM ET on the trade date.
Does FINRA's short volume include exchange trades?
No. The files cover trades reported to FINRA's facilities. For a full picture you'd have to add each exchange's own data, which is exactly what FINRA's 20% to 10.7% example shows.
Is off-exchange volume mostly retail?
A large part of it is retail orders filled by wholesalers, but it also includes institutional trades in dark pools and dealer trades. That mix is why "off-exchange" and "dark pool" shouldn't be used as synonyms.
Sources
- FINRA, Short Sale Volume: what the data covers, that it isn't short interest, and that it isn't consolidated with exchange data.
- FINRA, Daily Short Sale Volume Files: per-facility and consolidated files, posted by 6:00 PM ET on the trade date.
- FINRA, Understanding Short Sale Volume Data on FINRA's Website (May 10, 2019): the 20% to 10.7% example and the facilitation trade that leaves offsetting buys out.
- FINRA Regulatory Notice 19-29: separate ATS and non-ATS volume data, with two-week and four-week delays.
- SEC fact sheet, Proposed Rule to Enhance Order Competition (2022): more than 90% of retail marketable orders routed to wholesalers.
- Dark pool and block prints on 2026-10-30: 13,984 prints worth $277.16B, $107.38B of it in dark pools.
- Most traded in dark pools and blocks: QQQ ($16.44B), SPY ($14.91B), NVDA ($9.47B), AAPL ($9.03B), MSFT ($6.76B).
Updated 2026-11-02 16:04 UTC