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  <cov:submissionType>ATS-N/MA</cov:submissionType>
  <cov:rbOperatesPursuantToFormATS>N</cov:rbOperatesPursuantToFormATS>
  <cov:accessionNumber>0000310607-25-000037</cov:accessionNumber>
  <cov:filerCredentials>
    <cov:filerCik>0000310607</cov:filerCik>
    <cov:filerCcc>XXXXXXXX</cov:filerCcc>
  </cov:filerCredentials>
  <cov:fileNumber>013-00105</cov:fileNumber>
  <cov:txNMSStockATSName>CBX</cov:txNMSStockATSName>
  <cov:taStatementAboutAmendment>This material amendment will enable Subscribers within a MOC Hosted Pool to control whether orders may execute against each other on an order-by-order basis in addition to the existing ability to prevent self-crossing at the terminal ID level. Changes in Part III Items 11(c) and 14 (a) indicate that MOC Hosted Pool Subscribers may add a custom FIX value to orders that will act as a trade prevention key.  Orders tagged with the same custom FIX value cannot execute against each other in the same MOC Hosted Pool.  The changes herein apply to all Subscribers and the Broker-Dealer operator. </cov:taStatementAboutAmendment>
  <cov:liveTestFlag>LIVE</cov:liveTestFlag>
  <cov:flags>
    <cov:overrideInternetFlag>false</cov:overrideInternetFlag>
    <cov:confirmingCopyFlag>false</cov:confirmingCopyFlag>
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</cov:edgarSubmission>