EXHIBIT NO. 99.(a) 45
MFS SERIES TRUST X
CERTIFICATION OF AMENDMENT
TO THE DECLARATION OF TRUST
REDESIGNATION OF SERIES
Pursuant to Sections 6.11 and 9.3(a) of the Amended and Restated Declaration of Trust dated December 16, 2004, as amended (the “Declaration”), of MFS Series Trust X, a business trust organized under the laws of The Commonwealth of Massachusetts (the “Trust”), the undersigned, constituting a majority of the Trustees of the Trust, hereby redesignate an existing series of Shares (as defined in the Declaration) as follows:
The series designated as MFS International Intrinsic Value Fund shall be redesignated as MFS International Intrinsic Equity Fund.
Pursuant to Section 10.1 of the Declaration, this redesignation of series of Shares shall be effective on or about April 30, 2026.
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IN WITNESS WHEREOF, a majority of the Trustees of the Trust have executed this amendment, in one or more counterparts, all constituting a single instrument, as an instrument under seal in The Commonwealth of Massachusetts, as of April 30, 2026 and further certify, as provided by the provisions of Section 9.3(c) of the Declaration, that this amendment was duly adopted by the undersigned in accordance with Section 9.3(a) of the Declaration.
/s/STEVEN E. BULLER Steven E. Buller c/o MFS Investment Management 111 Huntington Avenue | /s/CLARENCE OTIS, JR. Clarence Otis, Jr. MFS Investment Management 111 Huntington Avenue Boston, MA 02199 |
/s/JOHN A. CAROSELLI John A. Caroselli c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 | /s/MICHAEL W. ROBERGE Michael W. Roberge c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 |
/s/MAUREEN R. GOLDFARB Maureen R. Goldfarb c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 | /s/MARYANNE L. ROEPKE Maryanne L. Roepke MFS Investment Management 111 Huntington Avenue Boston, MA 02199 |
/s/PETER D. JONES Peter D. Jones c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 | /s/PAULA E. SMITH Paula E. Smith MFS Investment Management 111 Huntington Avenue Boston, MA 02199 |
/s/JOHN P. KAVANAUGH John P. Kavanaugh c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 | /s/LAURIE J. THOMSEN Laurie J. Thomsen c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 |
/s/JAMES W. KILMAN, JR. James W. Kilman, Jr. c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 | /s/DARRELL A. WILLIAMS Darrell A. Williams c/o MFS Investment Management 111 Huntington Avenue Boston, MA 02199 |
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