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      <reportCalendarYear>2024</reportCalendarYear>
      <reportingPerson>
        <name>MFS SERIES TRUST I</name>
        <phoneNumber>617-954-5000</phoneNumber>
        <address>
          <com:street1>111 Huntington Ave</com:street1>
          <com:street2>21St Floor</com:street2>
          <com:city>Boston</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02199</com:zipCode>
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      <explanatoryInformation>
        <explanatoryChoice>Y</explanatoryChoice>
        <explanatoryNotes>"There may be instances in this report where a voting instruction is not included for a ballot item at a meeting. This typically occurs when the item is not an item for which a vote is requested (e.g., the receipt of a report by the company's management or board or the opening or closing of the meeting)."</explanatoryNotes>
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      <reportingPerson>MFS SERIES TRUST I</reportingPerson>
      <txSignature>David DiLorenzo</txSignature>
      <txPrintedSignature>David DiLorenzo</txPrintedSignature>
      <txTitle>President and Principal Executive Officer</txTitle>
      <txAsOfDate>08/27/2024</txAsOfDate>
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