BATS Notification of System Issue

January 09, 2013 18:39:43

Dear Member,

Please be advised that, as announced January 9, 2013, BATS has determined that upon an NBBO update on BATS' BYX Exchange, BZX Exchange and BATS Options, there are certain cases where the Matching Engine will allow for a trade through or an execution of a short sale order at a price that is equal to or less than the NBB when a short sale circuit breaker is in effect under Regulation SHO. These cases result from the sequencing of certain required events in the Matching Engine related to re-pricing and sliding orders in response to the NBBO update.

REVISED (1/25/2013): After further analysis, BATS has determined that more than 97% of the originally reported executions were not trade throughs under Rule 611 of Regulation NMS because they involved trades through quotes that had existed for less than one second or were priced below $1 and were within $.01 of the protected quote. Consequently, less than 12,000 trades have been confirmed to constitute trade throughs under Rule 611 across all three BATS US markets during the affected period. The updated numbers are below.

In the first case, a visible order that is posted and has been price slid can execute at a price that trades through another market center's protected quote if that away market center locks the displayed price of the BATS order and then BATS receives another order that crosses the working price of the resting order.

In the second case, the system was programmed to allow non-displayed peg orders to re-price in response to a change in the NBBO prior to sliding previously booked contra-side hidden orders that now cross an away market center. As a result, it is possible that in response to a change in the NBBO, the price of a resting hidden order could be crossing the NBBO momentarily and an execution could occur at that crossing price against a peg order that is re-priced in response to the NBBO change, resulting in a trade through. This particular issue can also result in a short sale order executing at a price that is equal to or less than the NBB while a Regulation SHO circuit breaker is in effect.

These system compliance issues have resulted in the following incidents:
Trade Throughs
BATS Options
(02/26/10 - 01/24/13)
Average Daily Incidents: 0.4
Total Incidents: 300

BYX Exchange
(10/15/10 - 01/24/13)
Average Daily Incidents: 0.6
Total Incidents: 348

BZX Exchange
(10/24/08 - 01/24/13)
Average Daily Incidents: 10.5
Total Incidents: 11,215

Regulation SHO Incidents
BYX Exchange
(02/28/11 - 01/04/13)
Total Incidents: 174

BZX Exchange
(02/28/11 - 01/04/13)
Total Incidents: 3,489

BATS deployed a permanent change to correct this system issue on January 25, 2013, in conjunction with its associated SEC rule filing.

Please contact the BATS Trade Desk or your Director of Sales with any questions.