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<PAGE> PAGE 7
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<PAGE> PAGE 11
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<PAGE> PAGE 12
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<PAGE> PAGE 14
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<PAGE> PAGE 16
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<PAGE> PAGE 19
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<PAGE> PAGE 21
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<PAGE> PAGE 22
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<PAGE> PAGE 23
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<PAGE> PAGE 24
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<PAGE> PAGE 25
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<PAGE> PAGE 26
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<PAGE> PAGE 27
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<PAGE> PAGE 28
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<PAGE> PAGE 29
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<PAGE> PAGE 30
SIGNATURE ELLEN MOYNIHAN
TITLE ASSISTANT TREASURER
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<NET-CHANGE-IN-ASSETS> 1005028
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 1901
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 28305
<AVERAGE-NET-ASSETS> 996875
<PER-SHARE-NAV-BEGIN> 10.00
<PER-SHARE-NII> 0.18
<PER-SHARE-GAIN-APPREC> (0.21)
<PER-SHARE-DIVIDEND> (0.17)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.80
<EXPENSE-RATIO> 0.30
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000063075
<NAME> MFS SERIES TRUST IX
<SERIES>
<NUMBER> 044
<NAME> MFS RESEARCH BOND FUND CLASS I
<MULTIPLIER> 1
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> APR-30-1999
<PERIOD-START> JAN-04-1999
<PERIOD-END> APR-30-1999
<INVESTMENTS-AT-COST> 991515
<INVESTMENTS-AT-VALUE> 977695
<RECEIVABLES> 45113
<ASSETS-OTHER> 0
<OTHER-ITEMS-ASSETS> 3172
<TOTAL-ASSETS> 1025980
<PAYABLE-FOR-SECURITIES> 9970
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 16411
<TOTAL-LIABILITIES> 26381
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1019559
<SHARES-COMMON-STOCK> 15
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 603
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (6743)
<ACCUM-APPREC-OR-DEPREC> (13820)
<NET-ASSETS> 999599
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 18643
<OTHER-INCOME> 0
<EXPENSES-NET> (845)
<NET-INVESTMENT-INCOME> 17798
<REALIZED-GAINS-CURRENT> (6743)
<APPREC-INCREASE-CURRENT> (13820)
<NET-CHANGE-FROM-OPS> (2765)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (3)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 15
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 1005028
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 1901
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 28305
<AVERAGE-NET-ASSETS> 141
<PER-SHARE-NAV-BEGIN> 10.00
<PER-SHARE-NII> 0.18
<PER-SHARE-GAIN-APPREC> (0.23)
<PER-SHARE-DIVIDEND> (0.17)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.78
<EXPENSE-RATIO> 0.30
</TABLE>
INDEPENDENT AUDITORS' REPORT
To the Trustees and Shareholders of MFS Series Trust IX:
In planning and performing our audits of the financial statements of MFS Bond
Fund, MFS Limited Maturity Fund, MFS Municipal Limited Maturity Fund, MFS
Research Bond Fund, MFS Intermediate Investment Grade Bond Fund (series of MFS
Series Trust IX) (the "Trust") for the year ended April 30, 1999 (on which we
have issued our reports dated June 4, 1999), we considered its internal control,
including control activities for safeguarding securities, in order to determine
our auditing procedures for the purpose of expressing our opinions on the
financial statements and to comply with the requirements of Form N-SAR, and not
to provide assurance on the Trust's internal control.
The management of the Trust is responsible for establishing and maintaining
internal control. In fulfilling this responsibility, estimates and judgments by
management are required to assess the expected benefits and related costs of
controls. Generally, controls that are relevant to an audit pertain to the
entity's objective of preparing financial statements for external purposes that
are fairly presented in conformity with generally accepted accounting
principles. Those controls include the safeguarding of assets against
unauthorized acquisition, use or disposition.
Because of inherent limitations in any internal control, misstatements due to
error or fraud may occur and not be detected. Also, projections of any
evaluation of internal control to future periods are subject to the risk that
the internal control may become inadequate because of changes in conditions or
that the degree of compliance with policies or procedures may deteriorate.
Our consideration of the Trust's internal control would not necessarily disclose
all matters in the internal control that might be material weaknesses under
standards established by the American Institute of Certified Public Accountants.
A material weakness is a condition in which the design or operation of one or
more of the internal control components does not reduce to a relatively low
level the risk that misstatements caused by error or fraud in amounts that would
be material in relation to the financial statements being audited may occur and
not be detected within a timely period by employees in the normal course of
performing their assigned functions. However, we noted no matters involving the
Trust's internal control and its operation, including controls for safeguarding
securities, that we consider to be material weaknesses as defined above as of
April 30, 1999.
This report is intended solely for the information and use of management, the
Trustees of the Series, and the Securities and Exchange Commission and is not
intended to be and should not be used by anyone other than these specified
parties.
Deloitte & Touche LLP
June 4, 1999
SUB-ITEM 77C
MFS SERIES TRUST IX ON BEHALF OF:
MFS INTERMEDIATE INVESTMENT GRADE BOND FUND ("IBF")
MFS RESEARCH BOND FUND ("RBF")
Consent of Sole Shareholder
The sole shareholder of IBF and RBF, each a series of MFS Series Trust IX, (the
"Trust"), took action by unanimous written consent, as permitted by the Trust's
Declaration of Trust, on December 31, 1998 to approve the following:
Approval of Investment Advisory Agreements
VOTED: That the terms of the Investment Advisory Agreement dated December 31,
1998, by and between the Trust, on behalf of MFS Intermediate
Investment Grade Bond Fund, and MFS, be, and they hereby are,
ratified, confirmed and approved; and
FURTHER That the terms of the Investment Advisory Agreement dated
VOTED: December 31, 1998, by and between the Trust, on behalf of MFS Research
Bond Fund, and MFS, be, and they hereby are, ratified, confirmed and
approved.
Ratification of Selection of Auditors
VOTED: That the selection of Deloitte & Touche LLP, independent public
accountants, by the Board of Trustees of the Trust, pursuant to and
subject to the provisions of Section 32(a) of the Investment Company
Act of 1940 as the independent public accountants of the Trust on
behalf of each Fund to certify every financial statement certified by
an independent public accountant which is required by any law or
regulation to be filed by the Trust on behalf of each Fund in respect
of all or any part of the Fund's fiscal year ending April 30, 1999,
be, and it hereby is, ratified, confirmed and approved.
Approval of Master Distribution Plan
VOTED: That in the exercise of their business judgment made in the
best interests of shareholders of each class of shares of the Fund,
the terms of the Master Distribution Plan, be and hereby is ratified,
confirmed and approved.
<PAGE>
SUB-ITEM 77C
MFS SERIES TRUST IX ON BEHALF OF:
MFS MID CAP VALUE FUND ("MCV")
MFS LARGE CAP VALUE FUND ("MLV")
MFS HIGH QUALITY BOND FUND ("MQB")
Consent of Sole Shareholder
The sole shareholder of MCV, MLV, and MQB, each a series of MFS Series Trust IX,
(the "Trust"), took action by unanimous written consent, as permitted by the
Trust's Declaration of Trust, on April 30, 1999 to approve the following:
Approval of Investment Advisory Agreements
VOTED: That the terms of the Investment Advisory Agreement dated
April 30, 1999, by and between the Trust, on behalf of MFS
Mid Cap Value Fund, and Massachusetts Financial Services
Company ("MFS"), be, and they hereby are, ratified,
confirmed and approved;
FURTHER
VOTED: That the terms of the Investment Advisory Agreement dated April
30, 1999, by and between the Trust, on behalf of MFS Large Cap Value
Fund, and MFS, be, and they hereby are, ratified, confirmed and
approved; and
FURTHER
VOTED: That the terms of the Investment Advisory Agreement dated April
30, 1999, by and between the Trust, on behalf of MFS High Quality Bond
Fund, and MFS, be, and they hereby are, ratified, confirmed and
approved.
<PAGE>
Ratification of Selection of Auditors
VOTED: That the selection of Deloitte & Touche LLP, independent public
accountants, by the Board of Trustees of the Trust, pursuant to and
subject to the provisions of Section 32(a) of the Investment Company
Act of 1940 as the independent public accountants of the Trust on
behalf of each Fund to certify every financial statement certified by
an independent public accountant which is required by any law or
regulation to be filed by the Trust on behalf of each Fund in respect
of all or any part of the Fund's fiscal year ending April 30, 2000,
be, and it hereby is, ratified, confirmed and approved.
Approval of Master Distribution Plan
VOTED: That in the exercise of their business judgment made in the
best interests of shareholders of each class of shares of the
Fund, the terms of the Master Distribution Plan, be and hereby
is ratified, confirmed and approved.
SUB-ITEM 77-H
MFS SERIES TRUST IX ON BEHALF OF:
MFS INTERMEDIATE INVESTMENT GRADE BOND FUND (" IBF")
MFS RESEARCH BOND FUND ("RBF")
As of April 30, 1999, the following entities beneficially owning more
than 25% of any one Series' voting securities, thereby becoming controlling
entities of such Series, are those entities listed as follows:
<TABLE>
<S> <C> <C>
% OF
SHARES
SERIES OWNER AND ADDRESS OWNED
MFS Intermediate Investment Grade Bond Fund MFS Fund Distributors, Inc. 99.96%
Class A Shares C/o Massachusetts Financial Services Company
Attn: Thomas B. Hastings
500 Boylston Street - 15th Floor
Boston, MA 02116-3740
MFS Research Bond Fund MFS Fund Distributors Inc. 99.76%
Class A Shares C/o Massachusetts Financial Services Company
Attn: Thomas B. Hastings
500 Boylston Street - 15th Floor
Boston, MA 02116-3740
</TABLE>
Holders as of October 31, 1998, no longer, as of April 30, 1999,
beneficially owning more than 25% of any one Series' voting securities, thereby
ceasing to be controlling entities of such Series, are as follows:
NOT APPLICABLE FOR THIS REPORT
PERIOD BECAUSE THESE 2 FUNDS DID
NOT EXIST ON OCTOBER 31, 1998
SUB-ITEM 77Q1(a)
MFS SERIES TRUST IX
on behalf of MFS Mid Cap Value Fund
MFS Large Cap Value Fund
MFS High Quality Bond Fund
A Form of Certificate of Amendment to the Declaration of Trust - Establishment
and Designation of Series and Establishment and Designation of Classes to
designate MFS Mid Cap Value Fund, MFS Large Cap Value Fund, and MFS High Quality
Bond Fund is contained in Post-Effective Amendment No. 37 to the Registration
Statement (File Nos. 2-50409 and 811-2464) as filed with the Securities and
Exchange Commission via EDGAR on February 12, 1999. Such document is
incorporated herein by reference.
SUB-ITEM 77QI(e)
MFS SERIES TRUST IX
ON BEHALF OF
MFS MID CAP VALUE FUND
MFS LARGE CAP VALUE FUND
MFS HIGH QUALITY BOND FUND
(a) A Form of Investment Advisory Agreement dated April 30, 1999 executed on
behalf of MFS Mid Cap Value Fund is contained in Post-Effective Amendment
No. 37 to the Registration Statement (File Nos. 2-50409 and 811-2464) as
filed with the Securities and Exchange Commission via EDGAR on February 12,
1999. Such document is incorporated herein by reference.
(b) A Form of Investment Advisory Agreement dated April 30, 1999 executed on
behalf of MFS Large Cap Value Fund is contained in Post-Effective Amendment
No. 37 to the Registration Statement (File Nos. 2-50409 and 811-2464) as
filed with the Securities and Exchange Commission via EDGAR on February 12,
1999. Such document is incorporated herein by reference.
(c) A Form of Investment Advisory Agreement dated April 30, 1999 executed on
behalf of MFS High Quality Bond Fund is contained in Post-Effective
Amendment No. 37 to the Registration Statement (File Nos. 2-50409 and
811-2464) as filed with the Securities and Exchange Commission via EDGAR on
February 12, 1999. Such document is incorporated herein by reference.
