NYSE Pillar—richer Closing Auction transparency

September 6, 2019

The NYSE successfully completed its migration to the Pillar technology platform on August 22, 2019. NYSE Pillar delivers far superior execution and latency performance. It also provides traders with an enhanced information feed leading into the most important trading event of the day: the close. One significant enhancement to transparency is the addition of new “Unpaired” Quantity and side information in the Closing Auction informational imbalance messages. These fields provide additional context to Closing Auction order flow and deliver better market color on closing interest.

The Unpaired Quantity is the volume of buy interest priced at or better than the Reference Price that cannot be paired with better-priced and at-priced sell interest. The side of the Unpaired Quantity is the side with the greater quantity of shares eligible to trade at that Reference Price. This contrasts with the Imbalance Quantity, which shows the better-priced interest only (i.e., the Imbalance Quantity does not include volume at the Reference Price on the imbalance side). The NYSE has always provided the Imbalance Quantity calculation and, with Pillar, now provides the Unpaired Quantity and side.

Example

  • Reference price is $10.00 (based on NYSE Last Sale)
  • On-close interest consists of the following Limit On Close (LOC) orders:
B 1,000 @ $10.042,000 shares that can trade at $10.00
B 1,000 @ $10.00
S 300 @ $9.99

Imbalance Message

Symbol Reference Price Paired Qty Total Imbalance Qty Imbalance Side Continuous Book Clearing Price UnpairedQty UnpairedSide
XYZ 10.00 300 700 B 10.04 1,700 B

Unpaired Quantity Calculation

UnpairedQty + PairedQty = Aggregate Interest at Reference Price
1,700 300 2,000

Imbalance Quantity Calculation

Buy Interest Better Than Reference Price - Sell Interest at or Better Than Reference Price = Imbalance Quantity
1,000 300 700

How Do I See This?

These new fields are available on the existing NYSE direct data feeds carrying imbalance data. Please contact your market data provider for assistance seeing the new fields or accessing imbalance data. Further details can be found in the data documentation and the relevant NYSE rule.

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