Company:  MFS SERIES TRUST XI (EACVX)
Form Type:  497
Filing Date:  10/28/2021 
CIK:  0000911637 
Address:  111 HUNTINGTON AVENUE
21ST FLOOR
 
City, State, Zip:  BOSTON, Massachusetts 02199 
Telephone:  18006372929 
Fiscal Year:  12/31 
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  FORM 497
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      TRUSTEE OWNERSHIP