<SEC-DOCUMENT>0000897101-25-000549.txt : 20251002
<SEC-HEADER>0000897101-25-000549.hdr.sgml : 20251002
<ACCEPTANCE-DATETIME>20251002164157
ACCESSION NUMBER:		0000897101-25-000549
CONFORMED SUBMISSION TYPE:	SCHEDULE 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20251002
DATE AS OF CHANGE:		20251002

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MFS HIGH YIELD MUNICIPAL TRUST
		CENTRAL INDEX KEY:			0000809844
		ORGANIZATION NAME:           	
		EIN:				042950868
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1130

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-84331
		FILM NUMBER:		251369968

	BUSINESS ADDRESS:	
		STREET 1:		111 HUNTINGTON AVENUE
		STREET 2:		24TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199
		BUSINESS PHONE:		617-954-5000

	MAIL ADDRESS:	
		STREET 1:		111 HUNTINGTON AVENUE
		STREET 2:		24TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	COLONIAL MUNICIPAL INCOME TRUST
		DATE OF NAME CHANGE:	19920703

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SIT INVESTMENT ASSOCIATES INC
		CENTRAL INDEX KEY:			0000769317
		ORGANIZATION NAME:           	
		EIN:				411404829
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		3300 IDS CENTER
		STREET 2:		80 SOUTH EIGHTH STREET
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55402
		BUSINESS PHONE:		6123323223

	MAIL ADDRESS:	
		STREET 1:		3300 IDS CENTER
		STREET 2:		80 SOUTH EIGHTH STREET
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55402
</SEC-HEADER>
<DOCUMENT>
<TYPE>SCHEDULE 13G/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/schedule13g" xmlns:com="http://www.sec.gov/edgar/common">
  <headerData>
    <submissionType>SCHEDULE 13G/A</submissionType>
    <previousAccessionNumber>0000897101-25-000031</previousAccessionNumber>
    <filerInfo>
      <filer>
        <filerCredentials>
          <!-- Field: Pseudo-Tag; ID: Name; Data: SIT INVESTMENT ASSOCIATES INC -->
          <cik>0000769317</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>


    </filerInfo>
  </headerData>
  <formData>
    <coverPageHeader>
      <amendmentNo>1</amendmentNo>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <eventDateRequiresFilingThisStatement>09/30/2025</eventDateRequiresFilingThisStatement>
      <issuerInfo>
        <issuerCik>0000809844</issuerCik>
        <issuerName>MFS High Yield Municipal Trust</issuerName>
        <issuerCusip>59318E102</issuerCusip>
        <issuerPrincipalExecutiveOfficeAddress>
          <com:street1>111 Huntington Avenue</com:street1>
          <com:city>Boston</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02199</com:zipCode>
        </issuerPrincipalExecutiveOfficeAddress>
      </issuerInfo>
      <designateRulesPursuantThisScheduleFiled>
        <designateRulePursuantThisScheduleFiled>Rule 13d-1(b)</designateRulePursuantThisScheduleFiled>
      </designateRulesPursuantThisScheduleFiled>
    </coverPageHeader>
    <coverPageHeaderReportingPersonDetails>


      <reportingPersonName>Sit Investment Associates, Inc.</reportingPersonName>
      <memberGroup>b</memberGroup>
      <citizenshipOrOrganization>MN</citizenshipOrOrganization>
      <reportingPersonBeneficiallyOwnedNumberOfShares>
        <soleVotingPower>0.00</soleVotingPower>
        <sharedVotingPower>1045340.00</sharedVotingPower>
        <soleDispositivePower>0.00</soleDispositivePower>
        <sharedDispositivePower>1045340.00</sharedDispositivePower>
      </reportingPersonBeneficiallyOwnedNumberOfShares>
      <reportingPersonBeneficiallyOwnedAggregateNumberOfShares>1045340.00</reportingPersonBeneficiallyOwnedAggregateNumberOfShares>
      <aggregateAmountExcludesCertainSharesFlag>N</aggregateAmountExcludesCertainSharesFlag>
      <classPercent>4.1</classPercent>
      <typeOfReportingPerson>IA</typeOfReportingPerson>
    </coverPageHeaderReportingPersonDetails>
    <coverPageHeaderReportingPersonDetails>


      <reportingPersonName>Sit Fixed Income Advisors II, LLC</reportingPersonName>
      <memberGroup>b</memberGroup>
      <citizenshipOrOrganization>DE</citizenshipOrOrganization>
      <reportingPersonBeneficiallyOwnedNumberOfShares>
        <soleVotingPower>0.00</soleVotingPower>
        <sharedVotingPower>1045340.00</sharedVotingPower>
        <soleDispositivePower>0.00</soleDispositivePower>
        <sharedDispositivePower>1045340.00</sharedDispositivePower>
      </reportingPersonBeneficiallyOwnedNumberOfShares>
      <reportingPersonBeneficiallyOwnedAggregateNumberOfShares>1045340.00</reportingPersonBeneficiallyOwnedAggregateNumberOfShares>
      <aggregateAmountExcludesCertainSharesFlag>N</aggregateAmountExcludesCertainSharesFlag>
      <classPercent>4.1</classPercent>
      <typeOfReportingPerson>IA</typeOfReportingPerson>
    </coverPageHeaderReportingPersonDetails>
    <items>
      <item1>
        <issuerName>MFS High Yield Municipal Trust</issuerName>
        <issuerPrincipalExecutiveOfficeAddress>111 Huntington Avenue, Boston, Massachusetts 02199</issuerPrincipalExecutiveOfficeAddress>
      </item1>
      <item2>
        <filingPersonName>Sit Investment Associates, Inc.
Sit Fixed Income Advisors II, LLC</filingPersonName>
        <principalBusinessOfficeOrResidenceAddress>c/o Sit Investment Associates, Inc.
80 South Eighth Street, Suite 3300
Minneapolis, MN  55402</principalBusinessOfficeOrResidenceAddress>
        <citizenship>Sit Investment Associates, Inc.   Minnesota Corporation
Sit Fixed Income Advisors II, LLC    Delaware LLC</citizenship>
      </item2>
      <item3>
        <notApplicableFlag>N</notApplicableFlag>
        <typeOfPersonFiling>IA</typeOfPersonFiling>
      </item3>
      <item4>
        <amountBeneficiallyOwned>See response to item 9 on each cover page.</amountBeneficiallyOwned>
        <classPercent>See response to item 11 on each cover page.</classPercent>
        <numberOfSharesPersonHas>
          <solePowerOrDirectToVote>See response to item 5 on each cover page.</solePowerOrDirectToVote>
          <sharedPowerOrDirectToVote>See response to item 6 on each cover page.</sharedPowerOrDirectToVote>
          <solePowerOrDirectToDispose>See response to item 7 on each cover page.</solePowerOrDirectToDispose>
          <sharedPowerOrDirectToDispose>See response to item 8 on each cover page.


The ownership percentages reported are based on 25,492,782 shares of common stock outstanding as of May 31, 2025 as reported in the Issuer's Report on Form N-CSRS filed with the Securities Exchange Commission.

Sit Investment Associates, Inc. ("SIA") is an investment adviser registered under section 203 of the Investment Advisers Act of 1940.  Sit Fixed Income Advisors II, LLC ("SFI") is an investment adviser registered under section 203 of the Investment Advisers Act of 1940 and a subsidiary of SIA.  SIA and SFI provide investment management services to client accounts ("Accounts").  In their roles as investment advisers SIA and SFI possess shared voting and investment power over securities of the Issuer described in this schedule 13G owned by the Accounts and may be deemed to be the beneficial owner of such shares of the Issuer owned by the Accounts.  All securities reported in this schedule 13G are owned by the Accounts.  Pursuant to Rule 13d-4 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), SIA and SFI disclaim beneficial ownership of such securities.</sharedPowerOrDirectToDispose>
        </numberOfSharesPersonHas>
      </item4>
      <item5>
        <notApplicableFlag>N</notApplicableFlag>
        <classOwnership5PercentOrLess>Y</classOwnership5PercentOrLess>
      </item5>
      <item6>
        <notApplicableFlag>Y</notApplicableFlag>
      </item6>
      <item7>
        <notApplicableFlag>Y</notApplicableFlag>
      </item7>
      <item8>
        <notApplicableFlag>Y</notApplicableFlag>
      </item8>
      <item9>
        <notApplicableFlag>Y</notApplicableFlag>
      </item9>
      <item10>
        <notApplicableFlag>N</notApplicableFlag>
        <certifications>By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.</certifications>
      </item10>
    </items>
    <exhibitInfo>Exhibit A - Joint Filing Agreement</exhibitInfo>
    <signatureInformation>
      <reportingPersonName>Sit Investment Associates, Inc.</reportingPersonName>
      <signatureDetails>
        <signature>/s/ Paul E. Rasmussen</signature>
        <title>Paul Rasmussen / Vice President</title>
        <date>10/02/2025</date>
      </signatureDetails>
    </signatureInformation>
    <signatureInformation>
      <reportingPersonName>Sit Fixed Income Advisors II, LLC</reportingPersonName>
      <signatureDetails>
        <signature>/s/ Paul E. Rasmussen</signature>
        <title>Paul Rasmussen / Vice President</title>
        <date>10/02/2025</date>
      </signatureDetails>
    </signatureInformation>
  </formData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
