Broken Market Ignites Momentum In Stocks

Earlier today, just after the market open, the Directedge/BATS EDGX Exchange broke. This is what BATS said at 9:41 am:

Please be advised that BATS has halted trading on EDGX Exchange to investigate an issue related to platform modifications rolled out today. Will advise.

Surely it was a complete coincidence that just as BATS broke (again) the market soared, and peaked within minutes of BATS reopening at 10:20, when it blasted the following notification:

Please be advised that all issues at BATS EDGX Exchange have been resolved. All systems are operating normally.

And then, several hours after the surge, BATS was kind enough to provide us with the post-mortem:

Please be advised that BATS EDGX Exchange experienced an issue related to new functionality involving certain Price Adjust logic that went into effect today. The issue only occurred during a crossed market. All impacted members have already been notified. Upon identification of the issue, BATS halted trading on the EDGX Exchange market at 9:41:38 AM ET to investigate. A software issue was identified, a patch was applied and trading resumed as of 10:20:00 AM


ET.Additionally, please note that Members with a default port setting of 'P' (Price Adjust) will have their default port settings automatically updated to 'S' (Display Price Sliding) effective tomorrow. Members that wish to continue to default to Price Adjust price sliding behavior should contact the BATS Trade Desk.

Of course, what happened within EDGX is irrelevant. What is relevant is what happened in the market.


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BATS - Making Markets Better...


Or Making Markets Broken-er