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<cov:edgarSubmission xmlns:cov="http://www.sec.gov/edgar/atsn/cover" xmlns:ats="http://www.sec.gov/edgar/atsncommon">
  <cov:submissionType>ATS-N/MA</cov:submissionType>
  <cov:rbOperatesPursuantToFormATS>N</cov:rbOperatesPursuantToFormATS>
  <cov:accessionNumber>0001110644-26-000038</cov:accessionNumber>
  <cov:filerCredentials>
    <cov:filerCik>0001110644</cov:filerCik>
    <cov:filerCcc>XXXXXXXX</cov:filerCcc>
  </cov:filerCredentials>
  <cov:fileNumber>013-00078</cov:fileNumber>
  <cov:txNMSStockATSName>Liquidnet H2O ATS</cov:txNMSStockATSName>
  <cov:taStatementAboutAmendment>This filing is a material amendment to Part II, Item 5 of its Form ATS-N to capitalize Targeted Invitation as a defined term; and Item 7 to capitalize Targeted Invitation as a defined term, to make clear Customers are able to participate in Targeted Invitations, to delete the term qualifying, and the ability of Members and Customers to opt out receiving Targeted Invitations. This filing is also amending Part III, Item 5 to capitalize Targeted Invitation as a defined term; Item 7 to capitalize Targeted Invitation as a defined term and delete the reference to tiering of Liquidity Partners regarding priority; Item 11 to capitalize Targeted Invitation as a defined term and delete the reference to tiering of Liquidity Partners; Item 13 to capitalize Targeted Invitation as a defined term and delete the references to tiering of Liquidity Partners; Item 14 to capitalize Targeted Invitation as a defined term; and Item 15 to capitalize Targeted Invitation as a defined term, to remove the term qualifying for Member or Customer, to make clear Customers are able to participate in Targeted Invitations, to provide the sending trader with certain parameters to configure how the Targeted Invitation is distributed to recipients, to allow a Trader to set the display size, to delete the section regarding Additional Information Received by the Sender,  and provide LNI discretion to restrict the use of Targeted Invitations through ongoing analysis to monitor for indicators of misuse of information. The changes in this material amendment apply to all Subscribers and the Broker-Dealer Operator, except Part II, Item 7b and Part III, Item 15b, apply to Members and Customers and Part III, Items 7a, 11c, 13a, 13b, 13d applies to Liquidity Partners.</cov:taStatementAboutAmendment>
  <cov:liveTestFlag>LIVE</cov:liveTestFlag>
  <cov:flags>
    <cov:overrideInternetFlag>false</cov:overrideInternetFlag>
    <cov:confirmingCopyFlag>false</cov:confirmingCopyFlag>
  </cov:flags>
</cov:edgarSubmission>