Block Trades

08 — MARKET STRUCTURE

The lane on the right edge of the chart marks block trades in the underlying stock — institution-sized prints, each pinned to the price it actually crossed at. A bar's length is the dollar value of what traded there, scaled against the heaviest price on screen. Where several blocks hit the same price they stack into one bar, so a level that absorbed real size reads as one long mark while still showing what it was made of.

The biggest of them step onto the chart itself: each session's top eight prints by dollar value are drawn as diamonds at the price and minute they crossed, sized so that a diamond's area tracks the print's value — the largest of the day sets the scale, the rest follow in proportion. Same colour coding as the lane; hover any diamond for its value, share count, price, time and type. The lane stays the complete session record — the diamonds are the day's headline sizes, placed in context.

SPY chart with purple diamonds marking the session's largest block prints; a tooltip shows a $232.73M dark pool block — **13 Aug, SPY.** The purple diamonds are the session's top prints, on the chart itself. Hovering one opens the same tooltip as the lane: a **dark pool block** — **$232.73M**, 300,000 shares, at **775.78**, 11:39:27 ET, right where the morning rally first paused.

BLOCK PRINTS @ PRICECURRENT SESSION

Block trades lane showing dark pool and lit prints stacked at their traded prices

DARK BLOCK — off-exchange, resting DARK SWEEP — off-exchange, aggressive LIT BLOCK — on-exchange, resting LIT SWEEP — on-exchange, aggressive

READING THE COLOURS

Venue and intent, on two axes

Colour carries two things at once. Hue is where it traded — purple for dark pools, blue for lit exchanges. Brightness is how it traded — a sweep is brighter than a resting block, because a sweep crossed the spread to get filled and a block waited. So the aggressive prints announce themselves without needing a separate marker. Hover any bar for its value, share count, price, time and type.

WHAT QUALIFIES

Only genuine size

The lane is already filtered before it reaches the chart: $5M+ for SPY and QQQ, $2M+ for the rest. Nothing small enough to be noise is drawn, so every bar you see is a print worth asking about. The lane covers the current session only — it answers what size committed today, not where it sat last week.

ON IMPLIED FORWARD

SPY's prints, in index points

An index has no shares of its own, so Implied Forward carries the prints of its proxy: the same SPY block trades, re-based to index price levels. Dollar values are the SPY prints' own — the lane and the diamonds read identically on either chart.

◎ ONE PRINT, TWO PLACES

A bar in the lane is a receipt, not a forecast — size that already traded at that price. The biggest receipts are drawn on the chart as well, so the session below follows one print into both places: a diamond at the price and minute it crossed, a bar in the lane at its price.

SPY chart: purple diamonds marking the day's biggest prints, with a $231M dark pool block tooltip at 771.62 — **12 Aug, SPY.** The purple diamonds are the day's biggest prints, on the chart itself. Hovering the lowest one opens its receipt — a **dark pool block**, **$231.49M**, 300,000 shares, at **771.62**, 11:41:56 ET. In the lane on the right the same print is the bar at 771.62: **purple** for off-exchange, the deeper shade for a block rather than a sweep, and a **length** that is its dollar value, scaled against the heaviest price on screen. A record of where size traded, not a prediction.

Every level on this page is live right now.

Reading about a VC Line is one thing; watching price stall against today's is another. The same markers, block prints and key levels described above are drawn on the live SPY, QQQ, IWM, DIA, GLD and SLV charts.

Open the live chart Take the 2-minute tour

WHALECLUES · ETF INTELLIGENCE · section 8 of 10