The week of June 22 through June 26 printed $55.1 billion in overnight ATS notional across three venues. That is a 52% increase in average daily notional over the prior week. For the first time, we mapped that flow against the NYSE consolidated tape to give it scale.
The consolidated tape, published daily by the NYSE, captures every matched share across all U.S. equity venues: NYSE, NASDAQ, all four CBOE exchanges, IEX, every ATS, every TRF, every single-dealer platform. Tapes A, B, and C combined represent the definitive record of total U.S. equity volume. This week, the four-day total (Monday through Thursday, Friday pending) was 98.54 billion shares.
Against that backdrop, overnight ATS notional averaged 1.47% of consolidated tape activity. That number sounds small until you consider that the overnight session runs from roughly 8:00 PM to 9:30 AM ET, a 13.5-hour window, while the regular session is 6.5 hours. The overnight tape is not competing for share. It is operating in a window where the rest of the market is closed.
All five sessions ran above the 20-day average ($6.88B). Tuesday cleared 2.28x. Source: Sapinover 3-venue pipeline (BlueOcean + Bruce + Moon ATS).
01Against the Consolidated Tape
We pulled the NYSE consolidated tape data (Tapes A + B + C) for each day of the week. These numbers capture every matched share across every U.S. equity venue. Overnight ATS notional is a fraction of this total, but the intraweek variance tells a story the absolute number does not.
Top bar (blue): consolidated tape in shares. Bottom bar (green): overnight ATS in notional dollars. Tuesday's $15.66B hit 2.04% of tape. Wednesday dropped to 0.87%. The tape was relatively stable; the ATS swung 88% intraweek.
Regular-session volume was steady. Overnight volume swung 88% intraweek. The divergence is the signal.
While consolidated tape volume ranged from 21.2B to 27.5B shares/day, a 30% band, overnight ATS notional swung from $8.32B (Wednesday) to $15.66B (Tuesday), an 88% band. Institutional repositioning during extended hours did not spread evenly. It concentrated into specific sessions. And the session that attracted the most overnight flow (Tuesday) preceded the most meaningful intraday reversal of the week (Wednesday).
02Session Profile
The session-level breakdown reveals not just volume but character. Each overnight session carries a directional signature: the net timing differential in basis points and the percentage of symbols with a positive overnight indication.
| Session | Net TD (bps) | % Positive | Character |
|---|---|---|---|
| MON 6/22 | +6.2 | 35.0% | Near neutral |
| TUE 6/23 | -256.2 | 18.0% | Strong negative |
| WED 6/24 | +107.4 | 77.0% | Positive reversal |
| THU 6/25 | +303.5 | 71.7% | Continued positive |
| FRI 6/26 | -189.9 | 14.1% | Negative shift |
Tuesday's strong negative indication (-256.2 bps, only 18.0% positive) preceded Wednesday's reversal (+107.4 bps, 77.0% positive). The overnight tape signaled the turn before the regular session opened.
03The Trend Line
The 20-day trailing average for 3-venue overnight ATS notional stands at $6.88 billion. Every session this week ran above it. Tuesday cleared 2.28x. Even Wednesday's session, the week's lightest, still printed 1.21x baseline.
Prior week (Jun 15–18, shortened by Juneteenth): $7.25B daily average. This week: $11.02B daily average. The step-up was not gradual.
Context: the prior week was shortened by the Juneteenth holiday (June 19) and averaged $7.25 billion/day across four sessions. This week averaged $11.02 billion/day across five full sessions. A 52% week-over-week increase in average daily notional. The step function was abrupt, not incremental.
04Where the Dollars Went
The semiconductor theme was impossible to miss. Micron (MU) alone cleared $11.30 billion in overnight notional for the week. Six of the top 10 symbols by notional sat inside the memory and chip complex: MU, SOXL, SNDK, MUU, DRAM, and INTC. Combined, the semiconductor cluster accounted for over $26 billion in overnight flow.
All timing differentials for the top names were negative this week. MU: -53.0 bps. SOXL: -121.1 bps. KORU: -405.6 bps. Heavy overnight selling pressure concentrated in memory and leveraged semiconductor wrappers.
Technology and ETF categories are not mutually exclusive: SOXL ($5.90B) appears in both. The sector breakdown counts single-name equities in their GICS sector and ETFs separately.
Six of the top fifteen overnight names were semiconductor plays. All carried negative timing differentials. The overnight tape was positioning ahead of the regular session, not following it.
MU's $11.30 billion week is notable not just for its size but for its consistency. It was the top overnight name on four of five sessions. SOXL ran heavy on both sides (SOXS also active), which is consistent with retail traders rotating conviction on short timeframes through leveraged wrappers. KORU and EWY in the top ten reflect the Korea/Asia exposure that has become a persistent feature of the overnight tape.
05Venue Distribution
The 3-venue split remained lopsided in favor of BlueOcean, consistent with its dominant role in extended-hours liquidity provision. Bruce ATS continued its steady growth, now at 12.5% of weekly volume.
BlueOcean printed $47.09 billion across the week, with single-session peaks above $13.5 billion on Tuesday. Bruce ATS cleared $6.88 billion, its strongest week in the dataset. Moon ATS held its characteristic long tail of speculative and lower-cap names at $1.12 billion.
06What the Divergence Tells Us
The week of June 22 was the first where we mapped overnight ATS flow against the full consolidated tape. Three observations stand out:
▸ Regular-session volume was stable (21–27B shares/day). Overnight ATS volume swung 88% intraweek ($8.3B to $15.7B).
▸ Tuesday's overnight session hit 2.04% of consolidated tape and carried a -256.2 bps net overnight indication. Wednesday reversed.
▸ SPY fell 1.5% and QQQ fell 3.5% on the week. The overnight tape was active while equities sold off.
▸ The semiconductor cluster (MU, SOXL, SNDK, MUU, DRAM, INTC) absorbed over $26B. All carried negative timing differentials.
▸ Week-over-week average daily notional: $7.25B to $11.02B. A 52% increase, not driven by breadth but by concentration.
▸ The overnight ATS session operates in a 13.5-hour window when the rest of the market is closed. At 1.47% of tape, it is structurally significant.
The regular session has scale. The overnight session has signal. The two are not in competition. They are complementary views of the same market, and the divergence between them, when it occurs, is where the information lives.
This is the first time we have published the tape comparison. It will become a standing feature of the weekly report.
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