<Page>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM N-CSR
CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES
Investment Company Act file number 811-10597
---------------------------------------------
Tax-Managed Mid-Cap Core Portfolio
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(Exact name of registrant as specified in charter)
The Eaton Vance Building, 255 State Street, Boston, Massachusetts 02109
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(Address of principal executive offices) (Zip code)
Alan R. Dynner
The Eaton Vance Building, 255 State Street, Boston, Massachusetts 02109
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(Name and address of agent for service)
Registrant's telephone number, including area code: (617) 482-8260
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Date of fiscal year end: October 31, 2003
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Date of reporting period: April 30, 2003
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Form N-CSR is to be used by management investment companies to file reports
with the Commission not later than 10 days after the transmission to
stockholders of any report that is required to be transmitted to stockholders
under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1).
The Commission may use the information provided on Form N-CSR in its
regulatory, disclosure review, inspection, and policymaking roles.
A registrant is required to disclose the information specified by Form N-CSR,
and the Commission will make this information public. A registrant is not
required to respond to the collection of information contained in Form N-CSR
unless the Form displays a currently valid Office of Management and Budget
("OMB") control number. Please direct comments concerning the accuracy of the
information collection burden estimate and any suggestions for reducing the
burden to Secretary, Securities and Exchange Commission, 450 Fifth Street,
NW, Washington, DC 20549-0609. The OMB has reviewed this collection of
information under the clearance requirements of 44 U.S.C. Section 3507.
ITEM 1. REPORTS TO STOCKHOLDERS
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TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
PORTFOLIO OF INVESTMENTS (UNAUDITED)
COMMON STOCKS -- 97.5%
<Table>
<Caption>
SECURITY SHARES VALUE
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Advertising Agencies -- 2.3%
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Omnicom Group, Inc. 9,100 $ 563,290
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$ 563,290
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Airlines -- 0.9%
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SkyWest, Inc. 18,300 $ 234,057
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$ 234,057
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Banks - Regional -- 4.7%
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City National Corp. 5,000 $ 205,850
SouthTrust Corp. 9,900 265,924
Southwest Bancorporation of Texas,
Inc.(1) 12,300 417,954
Synovus Financial Corp. 13,800 268,686
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$ 1,158,414
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Basic Materials -- 1.7%
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Vulcan Materials Co. 11,800 $ 412,646
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$ 412,646
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Broadcasting and Radio -- 2.4%
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Cox Radio, Inc. Class A(1) 26,400 $ 602,184
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$ 602,184
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Business Services - Miscellaneous -- 7.6%
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ChoicePoint, Inc.(1) 14,266 $ 503,304
Fair Isaac Corp. 5,800 302,064
Fiserv, Inc.(1) 12,200 359,168
SEI Investments Co. 9,500 250,135
The Reynolds and Reynolds Co. Class A 16,100 463,841
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$ 1,878,512
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Computer Services -- 2.0%
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PeopleSoft, Inc.(1) 15,300 $ 229,959
SunGard Data Systems, Inc.(1) 12,000 258,000
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$ 487,959
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Computer Software -- 1.0%
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National Instruments Corp.(1) 7,600 $ 243,808
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$ 243,808
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<Caption>
SECURITY SHARES VALUE
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Computers - Integrated Systems -- 4.9%
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Adobe Systems, Inc. 11,900 $ 411,264
Affiliated Computer Services, Inc.(1) 8,700 414,990
Jack Henry & Associates, Inc. Class A 29,000 377,870
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$ 1,204,124
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Cosmetics and Toiletries -- 1.8%
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Alberto-Culver Co. Class A 9,500 $ 452,960
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$ 452,960
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Education -- 1.6%
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Education Management Corp.(1) 8,000 $ 390,560
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$ 390,560
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Electronics - Equipment / Instruments -- 1.7%
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Amphenol Corp. Class A(1) 9,300 $ 411,897
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$ 411,897
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Electronics - Semiconductors -- 3.1%
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Microchip Technology, Inc. 22,950 $ 477,131
QLogic Corp.(1) 6,400 281,536
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$ 758,667
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Engineering and Construction -- 2.3%
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Jacobs Engineering Group, Inc.(1) 13,700 $ 563,755
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$ 563,755
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Finance - Investment Management -- 6.9%
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Affiliated Managers Group, Inc.(1) 13,000 $ 602,030
Ambac Financial Group, Inc. 9,900 577,665
Legg Mason, Inc. 9,500 515,850
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$ 1,695,545
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Food - Wholesale / Distribution -- 2.3%
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Performance Food Group Co.(1) 16,000 $ 561,280
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$ 561,280
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Gas Distribution -- 1.1%
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Piedmont Natural Gas Co., Inc. 7,600 $ 283,936
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$ 283,936
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</Table>
SEE NOTES TO FINANCIAL STATEMENTS
12
<Page>
TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
PORTFOLIO OF INVESTMENTS (UNAUDITED) CONT'D
<Table>
<Caption>
SECURITY SHARES VALUE
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Healthcare Services -- 4.7%
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First Health Group Corp.(1) 20,300 $ 508,515
WellPoint Health Networks, Inc.(1) 8,700 660,678
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$ 1,169,193
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Household Products -- 1.0%
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Estee Lauder Companies Inc., (The),
Class A 7,400 $ 240,500
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$ 240,500
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Industrial Gases -- 1.9%
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Praxair, Inc. 8,000 $ 464,640
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$ 464,640
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Insurance -- 3.0%
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Ace Ltd. 22,200 $ 734,376
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$ 734,376
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Insurance Brokers -- 1.4%
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Arthur J. Gallagher & Co., Inc. 14,200 $ 354,858
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$ 354,858
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Manufacturing -- 7.6%
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Danaher Corp. 7,100 $ 489,758
Dover Corp. 21,100 606,414
Harsco Corp. 10,500 361,935
Nucor Corp. 10,000 408,500
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$ 1,866,607
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Medical - Hospitals -- 2.0%
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Health Management Associates, Inc. Class
A 29,700 $ 506,682
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$ 506,682
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Medical Products -- 2.7%
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Patterson Dental Co.(1) 9,600 $ 385,632
Renal Care Group, Inc.(1) 8,900 288,360
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$ 673,992
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Medical Services / Supplies -- 2.5%
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DENTSPLY International, Inc. 16,300 $ 610,435
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$ 610,435
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<Caption>
SECURITY SHARES VALUE
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Multi-Utilities -- 2.3%
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Questar Corp. 19,000 $ 573,800
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$ 573,800
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Office Electronics / Technology -- 1.0%
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Zebra Technologies Corp. Class A(1) 3,600 $ 240,012
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$ 240,012
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Oil and Gas - Exploration and Production -- 5.9%
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Apache Corp. 10,725 $ 614,006
Devon Energy Corp. 0 10
EOG Resources, Inc. 12,800 478,464
Newfield Exploration Co.(1) 10,600 364,534
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$ 1,457,014
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Publishing -- 1.2%
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The New York Times Co. Class A 6,500 $ 301,470
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$ 301,470
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Retail - Discount -- 1.9%
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Family Dollar Stores, Inc. 13,600 $ 464,984
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$ 464,984
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Retail - Restaurants -- 4.2%
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Brinker International, Inc.(1) 16,900 $ 536,575
Sonic Corp.(1) 18,400 496,984
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$ 1,033,559
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Retail - Specialty and Apparel -- 3.4%
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Bed Bath and Beyond, Inc.(1) 13,600 $ 537,336
Tiffany & Co. 10,700 296,818
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$ 834,154
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Telecommunications -- 1.1%
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CenturyTel, Inc. 9,500 $ 279,775
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$ 279,775
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</Table>
SEE NOTES TO FINANCIAL STATEMENTS
13
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TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
PORTFOLIO OF INVESTMENTS (UNAUDITED) CONT'D
<Table>
<Caption>
SECURITY SHARES VALUE
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Transportation -- 1.4%
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Expeditors International of Washington,
Inc. 9,900 $ 359,954
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$ 359,954
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Total Common Stocks
(identified cost $23,316,684) $24,069,599
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Total Investments -- 97.5%
(identified cost $23,316,684) $24,069,599
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Other Assets, Less Liabilities -- 2.5% $ 620,425
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Net Assets -- 100.0% $24,690,024
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</Table>
(1) Non-income producing security.
SEE NOTES TO FINANCIAL STATEMENTS
14
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TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
FINANCIAL STATEMENTS (UNAUDITED)
STATEMENT OF ASSETS AND LIABILITIES
<Table>
<Caption>
AS OF APRIL 30, 2003
Assets
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Investments, at value
(identified cost, $23,316,684) $24,069,599
Cash 1,168,681
Receivable for investments sold 179,538
Interest and dividends receivable 8,355
Prepaid expenses 15
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TOTAL ASSETS $25,426,188
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Liabilities
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Payable for investments purchased $ 717,419
Payable to affiliate for Trustees' fees 155
Accrued expenses 18,590
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TOTAL LIABILITIES $ 736,164
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NET ASSETS APPLICABLE TO INVESTORS'
INTEREST IN PORTFOLIO $24,690,024
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Sources of Net Assets
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Net proceeds from capital contributions
and withdrawals $23,937,109
Net unrealized appreciation (computed on
the basis of identified cost) 752,915
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TOTAL $24,690,024
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</Table>
STATEMENT OF OPERATIONS
<Table>
<Caption>
FOR THE SIX MONTHS ENDED
APRIL 30, 2003
Investment Income
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Dividends $ 86,797
Interest 1,331
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TOTAL INVESTMENT INCOME $ 88,128
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Expenses
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Investment adviser fee $ 85,264
Trustees' fees and expenses 197
Custodian fee 17,549
Legal and accounting services 9,773
Miscellaneous 135
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TOTAL EXPENSES $ 112,918
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NET INVESTMENT LOSS $ (24,790)
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Realized and Unrealized Gain (Loss)
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Net realized gain (loss) --
Investment transactions (identified
cost basis) $(1,208,996)
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NET REALIZED LOSS $(1,208,996)
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Change in unrealized appreciation
(depreciation) --
Investments (identified cost basis) $ 2,142,038
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NET CHANGE IN UNREALIZED APPRECIATION
(DEPRECIATION) $ 2,142,038
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NET REALIZED AND UNREALIZED GAIN $ 933,042
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NET INCREASE IN NET ASSETS FROM
OPERATIONS $ 908,252
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</Table>
SEE NOTES TO FINANCIAL STATEMENTS
15
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TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
FINANCIAL STATEMENTS CONT'D
STATEMENTS OF CHANGES IN NET ASSETS
<Table>
<Caption>
SIX MONTHS ENDED
INCREASE (DECREASE) APRIL 30, 2003 PERIOD ENDED
IN NET ASSETS (UNAUDITED) OCTOBER 31, 2002(1)
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From operations --
Net investment loss $ (24,790) $ (49,816)
Net realized loss (1,208,996) (577,498)
Net change in unrealized
appreciation (depreciation) 2,142,038 (1,389,123)
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NET INCREASE (DECREASE) IN NET ASSETS
FROM OPERATIONS $ 908,252 $ (2,016,437)
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Capital transactions --
Contributions $ 10,065,319 $ 19,978,729
Withdrawals (3,432,559) (913,290)
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NET INCREASE IN NET ASSETS FROM
CAPITAL TRANSACTIONS $ 6,632,760 $ 19,065,439
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NET INCREASE IN NET ASSETS $ 7,541,012 $ 17,049,002
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Net Assets
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At beginning of period $ 17,149,012 $ 100,010
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AT END OF PERIOD $ 24,690,024 $ 17,149,012
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</Table>
(1) For the period from the start of business, March 1, 2002, to October 31,
2002.
SEE NOTES TO FINANCIAL STATEMENTS
16
<Page>
TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
FINANCIAL STATEMENTS CONT'D
SUPPLEMENTARY DATA
<Table>
<Caption>
SIX MONTHS ENDED
APRIL 30, 2003 PERIOD ENDED
(UNAUDITED) OCTOBER 31, 2002(1)
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Ratios/Supplemental Data
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Ratios (As a percentage of
average daily net assets):
Expenses 1.07%(2) 1.68%(2)
Net investment loss (0.23)%(2) (0.81)%(2)
Portfolio Turnover 33% 13%
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TOTAL RETURN(3) 4.55% (14.72)%
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NET ASSETS, END OF PERIOD
(000'S OMITTED) $24,690 $17,149
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</Table>
(1) For the period from the start of business, March 1, 2002, to October 31,
2002.
(2) Annualized.
(3) Total return is not computed on an annualized basis.
SEE NOTES TO FINANCIAL STATEMENTS
17
<Page>
TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
NOTES TO FINANCIAL STATEMENTS (UNAUDITED)
1 Significant Accounting Policies
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Tax-Managed Mid-Cap Core Portfolio (the Portfolio) is registered under the
Investment Company Act of 1940, as amended, as a diversified open-end
management investment company. The Portfolio, which was organized as a trust
under the laws of the State of New York on December 10, 2001, seeks to
achieve long-term, after-tax returns by investing in a diversified portfolio
of common stocks of mid-cap companies. The Declaration of Trust permits the
Trustees to issue interests in the Portfolio. At April 30, 2003, the Eaton
Vance Tax-Managed Mid-Cap Core Fund held an approximate 35.2% interest in the
Portfolio and one other investor owned an interest greater than 10% that
equaled 64.5%. The following is a summary of significant accounting policies
consistently followed by the Portfolio in the preparation of its financial
statements. The policies are in conformity with accounting principles
generally accepted in the United States of America.
A Investment Valuation -- Marketable securities, including options, that are
listed on foreign or U.S. securities exchanges are valued at closing sale
prices on the exchange where such securities are principally traded.
Marketable securities listed in the NASDAQ National Market System are valued
at the NASDAQ official closing price. Unlisted or listed securities for which
closing sale prices are not available are generally valued at the mean
between the latest bid and ask prices. Futures positions on securities or
currencies are generally valued at closing settlement prices. Short-term debt
securities with a remaining maturity of 60 days or less are valued at
amortized cost, which approximates fair value. Other fixed income and debt
securities, including listed securities and securities for which price
quotations are available, will normally be valued on the basis of valuations
furnished by a pricing service. Investments for which valuations or market
quotations are unavailable are valued at fair value using methods determined
in good faith by or at the direction of the Trustees.
B Income -- Dividend income is recorded on the ex-dividend date for dividends
received in cash and/or securities. However, if the ex-dividend date has
passed, certain dividends from foreign securities are recorded as the
Portfolio is informed of the ex-dividend date. Interest income is recorded on
the accrual basis.
C Income Taxes -- The Portfolio is treated as a partnership for federal tax
purposes. No provision is made by the Portfolio for federal or state taxes on
any taxable income of the Portfolio because each investor in the Portfolio is
ultimately responsible for the payment of any taxes on its share of taxable
income. Since the Portfolio's investors include regulated investment
companies that invest all or substantially all of their assets in the
Portfolio, the Portfolio normally must satisfy the applicable source of
income and diversification requirements (under the Internal Revenue Code) in
order for its investors to satisfy them. The Portfolio will allocate at least
annually among its investors each investor's distributive share of the
Portfolio's net investment income, net realized capital gains, and any other
items of income, gain, loss, deduction or credit.
D Financial Futures Contract -- Upon entering a financial futures contract, the
Portfolio is required to deposit either in cash or securities an amount
(initial margin) equal to a certain percentage of the purchase price
indicated in the financial futures contract. Subsequent payments are made or
received by the Portfolio (margin maintenance) each day, dependent on daily
fluctuations in the value of the underlying security, and are recorded for
book purposes as unrealized gains or losses by the Portfolio. The Portfolio's
investment in financial futures contracts is designed to hedge against
anticipated future changes in price of current or anticipated Portfolio
positions. Should prices move unexpectedly, the Portfolio may not achieve the
anticipated benefits of the financial futures contracts and may realize a
loss.
E Put Options -- Upon the purchase of a put option by the Portfolio, the
premium paid is recorded as an investment, the value of which is
marked-to-market daily. When a purchased option expires, the Portfolio will
realize a loss in the amount of the cost of the option. When the Portfolio
enters into a closing sale transaction, the Portfolio will realize a gain or
loss depending on whether the sales proceeds from the closing sale
transaction are greater or less than the cost of the option. When the
Portfolio exercises a put option, settlement is made in cash. The risk
associated with purchasing options is limited to the premium originally paid.
F Securities Sold Short -- The Portfolio may sell a security short if it owns
at least an equal amount of the security sold short or another security
convertible or exchangeable for an equal amount of the security sold short.
Such transactions are done in anticipation of a decline in the market price
of the securities or in order to hedge portfolio positions. The Portfolio
will generally borrow the security sold in order to make delivery to the
buyer. Upon executing the transaction, the Portfolio records the proceeds as
deposits with brokers in the Statement of Assets and Liabilities and
establishes an offsetting payable for securities sold short for the
securities
18
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TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
NOTES TO FINANCIAL STATEMENTS (UNAUDITED) CONT'D
due on settlement. The proceeds are retained by the broker as collateral for
the short position. The liability is marked-to-market and the Portfolio is
required to pay the lending broker any dividend or interest income earned
while the short position is open. A gain or loss is recorded when the
security is delivered to the broker. The Portfolio may recognize a loss on
the transaction if the market value of the securities sold increases before
the securities are delivered.
G Foreign Currency Translation -- Investment valuations, other assets and
liabilities initially expressed in foreign currencies are converted each
business day into U.S. dollars based upon current exchange rates. Purchases
and sales of foreign investment securities and income and expenses are
converted into U.S. dollars based upon currency exchange rates prevailing on
the respective dates of such transactions. Recognized gains or losses on
investment transactions attributable to foreign currency exchange rates are
recorded for financial statement purposes as net realized gains and losses on
investments. That portion of unrealized gains and losses on investments that
results from fluctuations in foreign currency exchange rates is not
separately disclosed.
H Expense Reduction -- Investors Bank & Trust Company (IBT) serves as custodian
of the Portfolio. Pursuant to the custodian agreement, IBT receives a fee
reduced by credits which are determined based on the average daily cash
balances the Portfolio maintains with IBT. All significant credit balances
used to reduce the Portfolio's custodian fees are reported as a reduction of
expenses on the Statement of Operations.
I Use of Estimates -- The preparation of the financial statements in conformity
with accounting principles generally accepted in the United States of America
requires management to make estimates and assumptions that affect the
reported amounts of assets and liabilities at the date of the financial
statements and the reported amounts of income and expense during the
reporting period. Actual results could differ from those estimates.
J Other -- Investment transactions are accounted for on a trade date basis.
K Interim Financial Statements -- The interim financial statements relating to
April 30, 2003 and for the six months then ended have not been audited by
independent certified public accountants, but in the opinion of the
Portfolio's management reflect all adjustments, consisting only of normal
recurring adjustments, necessary for the fair presentation of the financial
statements.
2 Investment Adviser Fee and Other Transactions with Affiliates
- -------------------------------------------
The investment adviser fee is earned by Boston Management and Research (BMR),
a wholly-owned subsidiary of Eaton Vance Management (EVM), as compensation
for management and investment advisory services rendered to the Portfolio.
Under the advisory agreement, BMR receives a monthly advisory fee equal to
0.80% annually of the average daily net assets of the Portfolio up to $500
million, and at reduced rates as daily net assets exceed that level. For the
six months ended April 30, 2003, the advisory fee amounted to $85,264.
Pursuant to a sub-advisory agreement, BMR has delegated the investment
management of the Portfolio to Atlanta Capital Management Company, LLC
(Atlanta Capital), a majority-owned subsidiary of Eaton Vance. BMR pays
Atlanta Capital a monthly fee for sub-advisory services provided to the
Portfolio equal to 0.55% annually of the average daily net assets up to $500
million, and at reduced rates as daily net assets exceed that level. Except
for Trustees of the Portfolio who are not members of EVM's or BMR's
organization, officers and Trustees receive remuneration for their services
to the Portfolio out of the investment adviser fee. Trustees of the Portfolio
that are not affiliated with BMR may elect to defer receipt of all or a
percentage of their annual fees in accordance with the terms of the Trustees
Deferred Compensation Plan. For the six months ended April 30, 2003, no
significant amounts have been deferred.
Certain officers and Trustees of the Portfolio are officers of the above
organizations.
3 Investment Transactions
- -------------------------------------------
Purchases and sales of investments, other than short-term obligations,
aggregated $12,921,215 and $6,797,619, respectively, for the six months ended
April 30, 2003.
19
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TAX-MANAGED MID-CAP CORE PORTFOLIO AS OF APRIL 30, 2003
NOTES TO FINANCIAL STATEMENTS (UNAUDITED) CONT'D
4 Federal Income Tax Basis of Unrealized Appreciation (Depreciation)
- -------------------------------------------
The cost and unrealized appreciation (depreciation) in value of the
investments owned at April 30, 2003, as computed on a federal income tax
basis, were as follows:
<Table>
AGGREGATE COST $23,316,684
-----------------------------------------------------
Gross unrealized appreciation $ 1,514,626
Gross unrealized depreciation (761,711)
-----------------------------------------------------
NET UNREALIZED APPRECIATION $ 752,915
-----------------------------------------------------
</Table>
5 Financial Instruments
- -------------------------------------------
The Portfolio may trade in financial instruments with off-balance sheet risk
in the normal course of its investing activities to assist in managing
exposure to various market risks. These financial instruments include written
options, forward foreign currency exchange contracts, and financial futures
contracts and may involve, to a varying degree, elements of risk in excess of
the amounts recognized for financial statement purposes.
The notional or contractual amounts of these instruments represent the
investment the Portfolio has in particular classes of financial instruments
and does not necessarily represent the amounts potentially subject to risk.
The measurement of the risks associated with these instruments is meaningful
only when all related and offsetting transactions are considered. The
Portfolio did not have any open obligations under these financial instruments
at April 30, 2003.
6 Line of Credit
- -------------------------------------------
The Portfolio participates with other portfolios and funds managed by BMR and
EVM and its affiliates in a $150 million unsecured line of credit agreement
with a group of banks. Borrowings will be made by the Portfolio solely to
facilitate the handling of unusual and/or unanticipated short-term cash
requirements. Interest is charged to each participating portfolio or fund
based on its borrowings at an amount above either the Eurodollar rate or
Federal Funds rate. In addition, a fee computed at an annual rate of 0.10% on
the daily unused portion of the line of credit is allocated among the
participating portfolios and funds at the end of each quarter. The Portfolio
did not have any significant borrowings or allocated fees for the six months
ended April 30, 2003.
20
<Page>
INVESTMENT MANAGEMENT
TAX-MANAGED MID-CAP CORE PORTFOLIO
Officers
James B. Hawkes
President and Trustee
Thomas E. Faust Jr.
Vice President
William R. Hackney, III
Vice President
Paul J. Marshall
Vice President
Charles B. Reed
Vice President
Michelle A. Alexander
Treasurer
Alan R. Dynner
Secretary
Trustees
Jessica M. Bibliowicz
Donald R. Dwight
Samuel L. Hayes, III
William H. Park
Norton H. Reamer
Lynn A. Stout
21
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ITEM 2. CODE OF ETHICS
Not Required in Filing.
ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT
Not Required in Filing.
ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES.
Not Required in Filing.
ITEMS 5-6. [RESERVED]
<Page>
ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END
MANAGEMENT INVESTMENT COMPANIES
Not Required in Filing.
ITEM 8. [RESERVED]
ITEM 9. CONTROLS AND PROCEDURES
(a) It is the conclusion of the registrant's principal executive officer and
principal financial officer that the effectiveness of the registrant's current
disclosure controls and procedures (such disclosure controls and procedures
having been evaluated within 90 days of the date of this filing) provide
reasonable assurance that the information required to be disclosed by the
registrant has been recorded, processed, summarized and reported within the time
period specified in the Commission's rules and forms and that the information
required to be disclosed by the registrant has been accumulated and communicated
to the registrant's principal executive officer and principal financial officer
in order to allow timely decisions regarding required disclosure.
(b) There have been no significant changes in the registrant's internal controls
or in other factors that could significantly affect these controls subsequent to
the date of their evaluation, including any corrective actions with regard to
significant deficiencies and material weaknesses.
ITEM 10. EXHIBITS
(a) and (b) Exhibit is attached to Filing.
(c) Exhibit is attached to Filing.
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934 and the
Investment Company Act of 1940, the registrant has duly caused this report to be
signed on its behalf by the undersigned, thereunto duly authorized.
TAX-MANAGED MID-CAP CORE PORTFOLIO
By: /s/ James B. Hawkes
-----------------------------
James B. Hawkes
President
Date: June 18, 2003
-----------------------------
<Page>
Pursuant to the requirements of the Securities Exchange Act of 1934 and the
Investment Company Act of 1940, this report has been signed below by the
following persons on behalf of the registrant and in the capacities and on the
dates indicated.
By: /s/ Michelle A. Alexander
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Michelle A. Alexander
Treasurer
Date: June 18, 2003
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By: /s/ James B. Hawkes
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James B. Hawkes
President
Date: June 18, 2003
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