<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019fb42f-387f-70ed-9481-1df5319d8c04,g:2ba89b84-adca-4392-935d-a2246c55e91f-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item"/>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/BalanceSheetsUnaudited" xlink:type="simple" xlink:href="itg-20260630.xsd#BalanceSheetsUnaudited"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/BalanceSheetsUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019fb4ed-e8f1-7843-99a0-c9d246f36203" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Cash_019fb4ed-e8f1-719e-9c4c-3e9d77b93043" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Cash"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7843-99a0-c9d246f36203" xlink:to="loc_us-gaap_Cash_019fb4ed-e8f1-719e-9c4c-3e9d77b93043" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019fb4ed-e8f1-75a3-bdf4-72cb06931c51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_019fb4ed-e8f1-79f2-8611-ddb42a973db1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019fb4ed-e8f1-75a3-bdf4-72cb06931c51" xlink:to="loc_us-gaap_CommonStockValue_019fb4ed-e8f1-79f2-8611-ddb42a973db1" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETSUnaudited" xlink:type="simple" xlink:href="itg-20260630.xsd#CONDENSEDCONSOLIDATEDBALANCESHEETSUnaudited"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETSUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7d5b-b3aa-168cca088bec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_019fb4ed-e8f1-75c8-b364-185a0c81b364" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7d5b-b3aa-168cca088bec" xlink:to="loc_us-gaap_AccountsPayableCurrent_019fb4ed-e8f1-75c8-b364-185a0c81b364" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-7217-b7c2-3600237e82e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7d5b-b3aa-168cca088bec" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-7217-b7c2-3600237e82e6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_019fb4ed-e8f1-7a6f-867e-df56f9e723f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7d5b-b3aa-168cca088bec" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_019fb4ed-e8f1-7a6f-867e-df56f9e723f7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityCurrent_019fb4ed-e8f1-79eb-801b-2e3806ebde7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7d5b-b3aa-168cca088bec" xlink:to="loc_us-gaap_FinanceLeaseLiabilityCurrent_019fb4ed-e8f1-79eb-801b-2e3806ebde7a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLongTermDebtCurrent_019fb4ed-e8f1-7196-90f5-fc4fdd167712" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLongTermDebtCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7d5b-b3aa-168cca088bec" xlink:to="loc_us-gaap_OtherLongTermDebtCurrent_019fb4ed-e8f1-7196-90f5-fc4fdd167712" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtCurrent_019fb4ed-e8f1-7d88-b9bd-0394ec50719a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredDebtCurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7d5b-b3aa-168cca088bec" xlink:to="loc_us-gaap_SecuredDebtCurrent_019fb4ed-e8f1-7d88-b9bd-0394ec50719a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019fb4ed-e8f1-7717-b6ed-32ffcc7ee224" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fb4ed-e8f1-7b6c-a9c4-de8291fd2675" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fb4ed-e8f1-7717-b6ed-32ffcc7ee224" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fb4ed-e8f1-7b6c-a9c4-de8291fd2675" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019fb4ed-e8f1-75a8-928d-5b15efe8d7ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fb4ed-e8f1-7717-b6ed-32ffcc7ee224" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019fb4ed-e8f1-75a8-928d-5b15efe8d7ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019fb4ed-e8f1-74df-93c5-270ad726e2c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetNetCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fb4ed-e8f1-7717-b6ed-32ffcc7ee224" xlink:to="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019fb4ed-e8f1-74df-93c5-270ad726e2c6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_019fb4ed-e8f1-7ddd-a4b5-1dc7144174ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fb4ed-e8f1-7717-b6ed-32ffcc7ee224" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_019fb4ed-e8f1-7ddd-a4b5-1dc7144174ec" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7a92-a7ab-fcf11989b611" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_LiabilitiesCurrent_019fb4ed-e8f1-7a92-a7ab-fcf11989b611" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLongTermDebtNoncurrent_019fb4ed-e8f1-7e02-b6f8-d7f61d3c423f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLongTermDebtNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_OtherLongTermDebtNoncurrent_019fb4ed-e8f1-7e02-b6f8-d7f61d3c423f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermLineOfCredit_019fb4ed-e8f1-767b-ba48-360c15e0d9eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermLineOfCredit"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_LongTermLineOfCredit_019fb4ed-e8f1-767b-ba48-360c15e0d9eb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredLongTermDebt_019fb4ed-e8f1-7512-b0f9-307629336e3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredLongTermDebt"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_SecuredLongTermDebt_019fb4ed-e8f1-7512-b0f9-307629336e3e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_019fb4ed-e8f1-7d09-9e82-f9013e5bd8c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_019fb4ed-e8f1-7d09-9e82-f9013e5bd8c2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_019fb4ed-e8f1-7333-952b-3bb076730f9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_019fb4ed-e8f1-7333-952b-3bb076730f9d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_019fb4ed-e8f1-7b32-82ec-6f745f206e72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_019fb4ed-e8f1-7b32-82ec-6f745f206e72" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_019fb4ed-e8f1-7b07-8dae-7f749b80bd6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_019fb4ed-e8f1-7b07-8dae-7f749b80bd6d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_019fb4ed-e8f1-7487-8dcc-e32894c566a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fb4ed-e8f1-7dac-b4eb-bd4e6195a199" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_019fb4ed-e8f1-7487-8dcc-e32894c566a7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fb4ed-e8f1-7add-966d-3f8e03fc39f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019fb4ed-e8f1-7a48-8865-827bd5f7d602" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fb4ed-e8f1-7add-966d-3f8e03fc39f7" xlink:to="loc_us-gaap_Liabilities_019fb4ed-e8f1-7a48-8865-827bd5f7d602" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_019fb4ed-e8f1-75d6-a08e-1c8f352c64cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fb4ed-e8f1-7add-966d-3f8e03fc39f7" xlink:to="loc_us-gaap_CommitmentsAndContingencies_019fb4ed-e8f1-75d6-a08e-1c8f352c64cc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MembersEquity_019fb4ed-e8f1-7570-aa27-2b7d332daf13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MembersEquity"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fb4ed-e8f1-7add-966d-3f8e03fc39f7" xlink:to="loc_us-gaap_MembersEquity_019fb4ed-e8f1-7570-aa27-2b7d332daf13" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019fb4ed-e8f1-7673-bf59-4075dc10890b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_AssetsCurrent_019fb4ed-e8f1-7673-bf59-4075dc10890b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_019fb4ed-e8f1-7a1e-b04a-766ffba3b40c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_019fb4ed-e8f1-7a1e-b04a-766ffba3b40c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_019fb4ed-e8f1-7d65-b60a-afb234212cb3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_019fb4ed-e8f1-7d65-b60a-afb234212cb3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseRightOfUseAsset_019fb4ed-e8f1-7d74-bc93-cd9649502c55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseRightOfUseAsset"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_FinanceLeaseRightOfUseAsset_019fb4ed-e8f1-7d74-bc93-cd9649502c55" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019fb4ed-e8f1-7a4c-b352-2d32b0250cab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_Goodwill_019fb4ed-e8f1-7a4c-b352-2d32b0250cab" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019fb4ed-e8f1-7786-9bf5-f9ae5995790d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019fb4ed-e8f1-7786-9bf5-f9ae5995790d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_019fb4ed-e8f1-73e3-80f8-c2999dc67210" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_019fb4ed-e8f1-73e3-80f8-c2999dc67210" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetNoncurrent_019fb4ed-e8f1-768c-8b16-c733510f399d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetNoncurrent"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fb4ed-e8f1-7be2-9132-0ee5710a8102" xlink:to="loc_us-gaap_AccountsReceivableNetNoncurrent_019fb4ed-e8f1-768c-8b16-c733510f399d" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSUnaudited" xlink:type="simple" xlink:href="itg-20260630.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSUnaudited"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fb4ed-e8f1-7ca4-ace8-b974f696e779" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fb4ed-e8f1-7aa6-8612-774b1b318d7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fb4ed-e8f1-7ca4-ace8-b974f696e779" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fb4ed-e8f1-7aa6-8612-774b1b318d7c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpenses_019fb4ed-e8f1-766f-a982-66e7e81e711d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpenses"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fb4ed-e8f1-7ca4-ace8-b974f696e779" xlink:to="loc_us-gaap_CostsAndExpenses_019fb4ed-e8f1-766f-a982-66e7e81e711d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019fb4ed-e8f1-71ad-aa92-dae68f88fbd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fb4ed-e8f1-7ca4-ace8-b974f696e779" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019fb4ed-e8f1-71ad-aa92-dae68f88fbd4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_019fb4ed-e8f1-76bb-b554-2f6628b1655c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fb4ed-e8f1-7ca4-ace8-b974f696e779" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_019fb4ed-e8f1-76bb-b554-2f6628b1655c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpenses_019fb4ed-e8f1-72f5-8fea-cff840fbc604" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpenses"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019fb4ed-e8f1-7d06-99e6-2d7efb92364c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fb4ed-e8f1-72f5-8fea-cff840fbc604" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019fb4ed-e8f1-7d06-99e6-2d7efb92364c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019fb4ed-e8f1-7900-b92a-dd0abfe07506" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fb4ed-e8f1-72f5-8fea-cff840fbc604" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019fb4ed-e8f1-7900-b92a-dd0abfe07506" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_019fb4ed-e8f1-7052-9eb9-0c618ebb82b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fb4ed-e8f1-72f5-8fea-cff840fbc604" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_019fb4ed-e8f1-7052-9eb9-0c618ebb82b4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_019fb4ed-e8f1-7029-9977-bced9b5a6cb2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fb4ed-e8f1-72f5-8fea-cff840fbc604" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_019fb4ed-e8f1-7029-9977-bced9b5a6cb2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fb4ed-e8f1-7d10-bf26-8a4aa746abbb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fb4ed-e8f1-75c8-8619-e27a8a149d1b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019fb4ed-e8f1-7d10-bf26-8a4aa746abbb" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fb4ed-e8f1-75c8-8619-e27a8a149d1b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019fb4ed-e8f1-73b5-b4c3-36259a8ff9ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019fb4ed-e8f1-7d10-bf26-8a4aa746abbb" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019fb4ed-e8f1-73b5-b4c3-36259a8ff9ec" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWSUnaudited" xlink:type="simple" xlink:href="itg-20260630.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWSUnaudited"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWSUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fb4ed-e8f1-75de-95ba-bfd7eb7003b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7128-ab1b-e2a602ec0c43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fb4ed-e8f1-75de-95ba-bfd7eb7003b1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7128-ab1b-e2a602ec0c43" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fb4ed-e8f1-7f52-80ba-59bda8a58b7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fb4ed-e8f1-75de-95ba-bfd7eb7003b1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fb4ed-e8f1-7f52-80ba-59bda8a58b7a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-71e6-8b8e-9e75e69fe044" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fb4ed-e8f1-75de-95ba-bfd7eb7003b1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-71e6-8b8e-9e75e69fe044" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fb4ed-e8f1-7ad2-9873-0b7127900d23" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_NetIncomeLoss_019fb4ed-e8f1-7ad2-9873-0b7127900d23" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation_019fb4ed-e8f1-7a4d-af85-afd71de48f24" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Depreciation"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_Depreciation_019fb4ed-e8f1-7a4d-af85-afd71de48f24" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_019fb4ed-e8f1-764a-b846-1fd84f9812c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_019fb4ed-e8f1-764a-b846-1fd84f9812c6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_019fb4ed-e8f1-7344-aee6-2027b7dcc660" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfFinancingCosts"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_019fb4ed-e8f1-7344-aee6-2027b7dcc660" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_019fb4ed-e8f1-7165-9d51-76d5596667c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_019fb4ed-e8f1-7165-9d51-76d5596667c6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_019fb4ed-e8f1-7261-b4a7-25a9941cc09d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_019fb4ed-e8f1-7261-b4a7-25a9941cc09d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_019fb4ed-e8f1-7cdb-8904-3e1687369729" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDispositionOfAssets1"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_GainLossOnDispositionOfAssets1_019fb4ed-e8f1-7cdb-8904-3e1687369729" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_019fb4ed-e8f1-7dde-9708-cf77b7f69984" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_019fb4ed-e8f1-7dde-9708-cf77b7f69984" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_019fb4ed-e8f1-7cb6-9a0a-622984f508eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_ShareBasedCompensation_019fb4ed-e8f1-7cb6-9a0a-622984f508eb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019fb4ed-e8f1-7ccf-9bc1-b48404d3a2e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc order="10" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019fb4ed-e8f1-7ccf-9bc1-b48404d3a2e9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset_019fb4ed-e8f1-7d8f-824a-144fddac5f06" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerAsset"/>
    <link:calculationArc order="11" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset_019fb4ed-e8f1-7d8f-824a-144fddac5f06" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_019fb4ed-e8f1-7868-bb56-1121875a3855" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets"/>
    <link:calculationArc order="12" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_019fb4ed-e8f1-7868-bb56-1121875a3855" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_019fb4ed-e8f1-7648-b164-a3493002b1e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities"/>
    <link:calculationArc order="13" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_019fb4ed-e8f1-7648-b164-a3493002b1e4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingLeaseLiability_019fb4ed-e8f1-73e7-8737-7693507b673c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOperatingLeaseLiability"/>
    <link:calculationArc order="14" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_IncreaseDecreaseInOperatingLeaseLiability_019fb4ed-e8f1-73e7-8737-7693507b673c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentForContingentConsiderationLiabilityOperatingActivities_019fb4ed-e8f1-7137-bc0d-1db9e5e28e2a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentForContingentConsiderationLiabilityOperatingActivities"/>
    <link:calculationArc order="15" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fb4ed-e8f1-7a49-9b01-71995b4b157e" xlink:to="loc_us-gaap_PaymentForContingentConsiderationLiabilityOperatingActivities_019fb4ed-e8f1-7137-bc0d-1db9e5e28e2a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fb4ed-e8f1-75a6-875c-70f3d9ad9441" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019fb4ed-e8f1-7874-9781-5f3c56a1237b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fb4ed-e8f1-75a6-875c-70f3d9ad9441" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019fb4ed-e8f1-7874-9781-5f3c56a1237b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_019fb4ed-e8f1-7cfc-a764-df4d2a60d373" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fb4ed-e8f1-75a6-875c-70f3d9ad9441" xlink:to="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_019fb4ed-e8f1-7cfc-a764-df4d2a60d373" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_019fb4ed-e8f1-784e-8212-09114ef5e5c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fb4ed-e8f1-75a6-875c-70f3d9ad9441" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_019fb4ed-e8f1-784e-8212-09114ef5e5c8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_itg_PaymentForAcquisitionAmountsDueToSellers_019fb4ed-e8f1-7498-b41d-06e410cc2c19" xlink:href="itg-20260630.xsd#itg_PaymentForAcquisitionAmountsDueToSellers"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_itg_PaymentForAcquisitionAmountsDueToSellers_019fb4ed-e8f1-7498-b41d-06e410cc2c19" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_019fb4ed-e8f1-7119-b13b-3b27366d0b3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_019fb4ed-e8f1-7119-b13b-3b27366d0b3a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfSecuredDebt_019fb4ed-e8f1-7859-bb44-47735b399eb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfSecuredDebt"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_RepaymentsOfSecuredDebt_019fb4ed-e8f1-7859-bb44-47735b399eb5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_019fb4ed-e8f1-7b2f-bb28-1b19a6118c1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_019fb4ed-e8f1-7b2f-bb28-1b19a6118c1a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_019fb4ed-e8f1-791b-8f45-1d5536a8e3b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfLongTermLinesOfCredit"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_019fb4ed-e8f1-791b-8f45-1d5536a8e3b0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeasePrincipalPayments_019fb4ed-e8f1-7f59-ab2b-86b970645ee3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeasePrincipalPayments"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_FinanceLeasePrincipalPayments_019fb4ed-e8f1-7f59-ab2b-86b970645ee3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfCapitalDistribution_019fb4ed-e8f1-71f1-8a73-68382f5ab8ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfCapitalDistribution"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_PaymentsOfCapitalDistribution_019fb4ed-e8f1-71f1-8a73-68382f5ab8ab" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt_019fb4ed-e8f1-7c12-b7c1-a49d2c296d3c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt_019fb4ed-e8f1-7c12-b7c1-a49d2c296d3c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfOtherLongTermDebt_019fb4ed-e8f1-7dc9-8ccb-20f742f807f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfOtherLongTermDebt"/>
    <link:calculationArc order="9" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_RepaymentsOfOtherLongTermDebt_019fb4ed-e8f1-7dc9-8ccb-20f742f807f6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDebtIssuanceCosts_019fd879-03c0-791c-8b25-2ba8af6a8b31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfDebtIssuanceCosts"/>
    <link:calculationArc order="10" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fb4ed-e8f1-7ec7-ae55-8ffde872022c" xlink:to="loc_us-gaap_PaymentsOfDebtIssuanceCosts_019fd879-03c0-791c-8b25-2ba8af6a8b31" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/CONTRACTASSETSDetails" xlink:type="simple" xlink:href="itg-20260630.xsd#CONTRACTASSETSDetails"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/CONTRACTASSETSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019fb4ed-e8f1-7ced-99b2-c814d7aa134a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetNetCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_itg_RetainageReceivablesCurrent_019fb4ed-e8f1-73d8-bd32-b9618e22fcb9" xlink:href="itg-20260630.xsd#itg_RetainageReceivablesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019fb4ed-e8f1-7ced-99b2-c814d7aa134a" xlink:to="loc_itg_RetainageReceivablesCurrent_019fb4ed-e8f1-73d8-bd32-b9618e22fcb9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnbilledReceivablesCurrent_019fb4ed-e8f1-7349-8130-064c2e6b37db" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnbilledReceivablesCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019fb4ed-e8f1-7ced-99b2-c814d7aa134a" xlink:to="loc_us-gaap_UnbilledReceivablesCurrent_019fb4ed-e8f1-7349-8130-064c2e6b37db" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/PROPERTYANDEQUIPMENTScheduleofPropertyandEquipmentDetails" xlink:type="simple" xlink:href="itg-20260630.xsd#PROPERTYANDEQUIPMENTScheduleofPropertyandEquipmentDetails"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/PROPERTYANDEQUIPMENTScheduleofPropertyandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_019fb4ed-e8f1-787c-bfaa-574af3cf6ad3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_019fb4ed-e8f1-744f-b85f-fc4303c3f737" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_019fb4ed-e8f1-787c-bfaa-574af3cf6ad3" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_019fb4ed-e8f1-744f-b85f-fc4303c3f737" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019fb4ed-e8f1-77da-b582-ef7bbf922a0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_019fb4ed-e8f1-787c-bfaa-574af3cf6ad3" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019fb4ed-e8f1-77da-b582-ef7bbf922a0b" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/INTANGIBLEASSETSScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="itg-20260630.xsd#INTANGIBLEASSETSScheduleofIntangibleAssetsDetails"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/INTANGIBLEASSETSScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019fb4ed-e8f1-73e0-958b-348f1105e891" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019fb4ed-e8f1-7daa-bc3a-313c80eac07d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019fb4ed-e8f1-73e0-958b-348f1105e891" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019fb4ed-e8f1-7daa-bc3a-313c80eac07d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019fb4ed-e8f1-7215-b1cc-022914978bcf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019fb4ed-e8f1-73e0-958b-348f1105e891" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019fb4ed-e8f1-7215-b1cc-022914978bcf" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/ACCRUEDEXPENSESDetails" xlink:type="simple" xlink:href="itg-20260630.xsd#ACCRUEDEXPENSESDetails"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/ACCRUEDEXPENSESDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_019fb4ed-e8f1-751e-9aee-ee5f1b768720" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_019fb4ed-e8f1-751e-9aee-ee5f1b768720" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedInsuranceCurrent_019fb4ed-e8f1-7a5b-9e1b-08c1fa411f10" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedInsuranceCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_us-gaap_AccruedInsuranceCurrent_019fb4ed-e8f1-7a5b-9e1b-08c1fa411f10" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestPayableCurrent_019fb4ed-e8f1-7382-9a2e-eac2f88fad41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestPayableCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_us-gaap_InterestPayableCurrent_019fb4ed-e8f1-7382-9a2e-eac2f88fad41" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesAndExciseTaxPayableCurrent_019fb4ed-e8f1-7dee-9fb7-994bf8000114" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SalesAndExciseTaxPayableCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_us-gaap_SalesAndExciseTaxPayableCurrent_019fb4ed-e8f1-7dee-9fb7-994bf8000114" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_019fb4ed-e8f1-75a3-b558-b3322139828c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_019fb4ed-e8f1-75a3-b558-b3322139828c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_itg_BusinessCombinationRecognizedLiabilityAssumedAccruedLiabilitiesCurrent_019fb4ed-e8f1-7787-a9f1-e9cea404e683" xlink:href="itg-20260630.xsd#itg_BusinessCombinationRecognizedLiabilityAssumedAccruedLiabilitiesCurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_itg_BusinessCombinationRecognizedLiabilityAssumedAccruedLiabilitiesCurrent_019fb4ed-e8f1-7787-a9f1-e9cea404e683" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_itg_AccruedOfferingCostsCurrent_019fb4ed-e8f1-78c5-9a6c-a1ba6874ec61" xlink:href="itg-20260630.xsd#itg_AccruedOfferingCostsCurrent"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_itg_AccruedOfferingCostsCurrent_019fb4ed-e8f1-78c5-9a6c-a1ba6874ec61" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent_019fc8ef-6752-776b-8505-eb9511d5d216" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAccruedLiabilitiesCurrent"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fb4ed-e8f1-791c-a3f4-f373a92ee239" xlink:to="loc_us-gaap_OtherAccruedLiabilitiesCurrent_019fc8ef-6752-776b-8505-eb9511d5d216" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://prod.itgcomm.com/role/LEASESScheduleofOperatingLeasesDetails" xlink:type="simple" xlink:href="itg-20260630.xsd#LEASESScheduleofOperatingLeasesDetails"/>
  <link:calculationLink xlink:role="http://prod.itgcomm.com/role/LEASESScheduleofOperatingLeasesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseCost_019fbf7a-615e-7e91-810d-edd0b13c8184" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeaseCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseCost_019fbf7a-615e-75d8-a75e-ebe0972a580e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseCost"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_019fbf7a-615e-7e91-810d-edd0b13c8184" xlink:to="loc_us-gaap_OperatingLeaseCost_019fbf7a-615e-75d8-a75e-ebe0972a580e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableLeaseCost_019fbf7a-615e-7ddc-87e5-c89aec7a29ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableLeaseCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_019fbf7a-615e-7e91-810d-edd0b13c8184" xlink:to="loc_us-gaap_VariableLeaseCost_019fbf7a-615e-7ddc-87e5-c89aec7a29ff" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermLeaseCost_019fbf7a-615e-7cc9-97f1-c6d47e2ffe27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermLeaseCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_019fbf7a-615e-7e91-810d-edd0b13c8184" xlink:to="loc_us-gaap_ShortTermLeaseCost_019fbf7a-615e-7cc9-97f1-c6d47e2ffe27" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
