Nanex Research

Nanex ~ 05-Jul-2013 ~ The NY-ARCA Dark Pool

Dark Pools report trades, but not quotes.

On July 5, 2013 between 7:20 and 8:42:50, quotes from NY-ARCA (PACF) stopped in dozens of  stocks, most notably large ETFs such as SPY and IWM. The charts below show quotes and trades from all exchanges in the symbol SPY. At 8:30, during the NY-ARCA quote outage, two important news items (Employment Situation and Jobless Claims) were released. Prices in SPY and other symbols (gold for example) were extremely volatile right before the news release.

Although quotes from NY-ARCA stopped, trade reports from that exchange continued as if nothing happened. This indicates the problem was with NY-ARCA sending quotes to the Consolidated Feed. Since trading continued, we know that direct feed (ArcaBook) customers weren't affected. By the way, this is a violation of Reg NMS, which prohibits exchanges from sending core information (time, price, size, etc.) to a direct feed faster than to the consolidated.

The charts show the NY-ARCA quote stoppage and its influence on  prices from other exchanges and dark pools. Note: charts use the mnemonic PACF to indicated NY-ARCA.

See also Gold Oscillations and Jumping the Gun which document unusual behavior in gold and emini futures during this period of time.

Update: NYSE acknowledges the outage.

Spreadsheet of 1,358 trades in 99 symbols (worth $20.9 million) from NY-ARCA that appear to have been reported late. These trades were grouped and sent in 2 batches: at 8:22:16 and 8:28:29. It is possible the second batch influenced a trading frenzy (5000 contracts in a second) in the eMini futures - click for charts.


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