EX-99.CERT
MFS SERIES TRUST XI
CERTIFICATION PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT
I, Tracy Atkinson, certify that:
1. I have reviewed this report on Form N-CSR of MFS Series Trust XI;
2. Based on my knowledge, this report does not contain any untrue statement of
a material fact or omit to state a material fact necessary to make the
statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;
3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects
the financial condition, results of operations, changes in net assets, and
cash flows (if the financial statements are required to include a statement
of cash flows) of the registrant as of, and for, the periods presented in
this report;
4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined
in Rule 30a-3(c) under the Investment Company Act of 1940) and internal
control over financial reporting (as defined in Rule 30a-3(d) under the
Investment Company Act of 1940) for the registrant and have:
a. Designed such disclosure controls and procedures, or caused such
disclosure controls and procedures to be designed under our
supervision, to ensure that material information relating to the
registrant, including its consolidated subsidiaries, is made known to
us by others within those entities, particularly during the period in
which this report is being prepared;
b. Designed such internal control over financial reporting, or caused such
internal control over financial reporting to be designed under our
supervision, to provide reasonable assurance regarding the reliability
of financial reporting and the preparation of financial statements for
external purposes in accordance with generally accepted accounting
principles;
c. Evaluated the effectiveness of the registrant's disclosure controls and
procedures and presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures as of a date
within 90 days prior to the filing date of this report based on such
evaluation; and
d. Disclosed in this report any change in the registrant's internal
control over financial reporting that occurred during the second fiscal
quarter of the period covered by the report that has materially
affected, or is reasonably likely to materially affect, the
registrant's internal control over financial reporting; and
5. The registrant's other certifying officer and I have disclosed to the
registrant's auditors and the audit committee of the registrant's board of
directors (or persons performing the equivalent functions):
a. All significant deficiencies and material weaknesses in the design or
operation of internal control over financial reporting which are
reasonably likely to adversely affect the registrant's ability to
record, process, summarize, and report financial information; and
b. Any fraud, whether or not material, that involves management or other
employees who have a significant role in the registrant's internal
control over financial reporting.
Date: November 15, 2007 TRACY ATKINSON
----------------- ---------------------------------------
Tracy Atkinson
Treasurer (Principal Financial Officer
and Accounting Officer)
EX-99.CERT
MFS SERIES TRUST XI
CERTIFICATION PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT
I, Maria F. Dwyer, certify that:
1. I have reviewed this report on Form N-CSR of MFS Series Trust XI;
2. Based on my knowledge, this report does not contain any untrue statement of
a material fact or omit to state a material fact necessary to make the
statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;
3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects
the financial condition, results of operations, changes in net assets, and
cash flows (if the financial statements are required to include a statement
of cash flows) of the registrant as of, and for, the periods presented in
this report;
4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined
in Rule 30a-3(c) under the Investment Company Act of 1940) and internal
control over financial reporting (as defined in Rule 30a-3(d) under the
Investment Company Act of 1940) for the registrant and have:
a. Designed such disclosure controls and procedures, or caused such
disclosure controls and procedures to be designed under our
supervision, to ensure that material information relating to the
registrant, including its consolidated subsidiaries, is made known to
us by others within those entities, particularly during the period in
which this report is being prepared;
b. Designed such internal control over financial reporting, or caused such
internal control over financial reporting to be designed under our
supervision, to provide reasonable assurance regarding the reliability
of financial reporting and the preparation of financial statements for
external purposes in accordance with generally accepted accounting
principles;
c. Evaluated the effectiveness of the registrant's disclosure controls and
procedures and presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures as of a date
within 90 days prior to the filing date of this report based on such
evaluation; and
d. Disclosed in this report any change in the registrant's internal
control over financial reporting that occurred during the second fiscal
quarter of the period covered by the report that has materially
affected, or is reasonably likely to materially affect, the
registrant's internal control over financial reporting; and
5. The registrant's other certifying officer and I have disclosed to the
registrant's auditors and the audit committee of the registrant's board of
directors (or persons performing the equivalent functions):
a. All significant deficiencies and material weaknesses in the design or
operation of internal control over financial reporting which are
reasonably likely to adversely affect the registrant's ability to
record, process, summarize, and report financial information; and
b. Any fraud, whether or not material, that involves management or other
employees who have a significant role in the registrant's internal
control over financial reporting.
Date: November 15, 2007 MARIA F. DWYER
----------------- ---------------------------------------
Maria F. Dwyer
President (Principal Executive Officer)
EX-99.906CERT
MFS SERIES TRUST XI
CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT
I, Tracy Atkinson, certify that, to my knowledge:
1. The Form N-CSR (the "Report") of MFS Series Trust XI (the "Registrant")
fully complies for the period covered by the Report with the requirements of
Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and
2. The information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the
Registrant.
Date: November 15, 2007 TRACY ATKINSON
----------------- ---------------------------------------
Tracy Atkinson
Treasurer (Principal Financial Officer
and Accounting Officer)
A SIGNED ORIGINAL OF THIS WRITTEN STATEMENT REQUIRED BY SECTION 906 HAS BEEN
PROVIDED TO THE REGISTRANT AND WILL BE RETAINED BY THE REGISTRANT AND FURNISHED
TO THE SECURITIES AND EXCHANGE COMMISSION OR ITS STAFF UPON REQUEST.
EX-99.906CERT
MFS SERIES TRUST XI
CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT
I, Maria F. Dwyer, certify that, to my knowledge:
1. The Form N-CSR (the "Report") of MFS Series Trust XI (the "Registrant")
fully complies for the period covered by the Report with the requirements of
Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and
2. The information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the
Registrant.
Date: November 15, 2007 MARIA F. DWYER
----------------- ---------------------------------------
Maria F. Dwyer
President (Principal Executive Officer)
A SIGNED ORIGINAL OF THIS WRITTEN STATEMENT REQUIRED BY SECTION 906 HAS BEEN
PROVIDED TO THE REGISTRANT AND WILL BE RETAINED BY THE REGISTRANT AND FURNISHED
TO THE SECURITIES AND EXCHANGE COMMISSION OR ITS STAFF UPON REQUEST.