<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: 811-10065
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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)
Alan R. Dynner
The Eaton Vance Building, 255 State Street, Boston, Massachusetts 02109
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(Name and Address of Agent for Services)
(617) 482-8260
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(Registrant's Telephone Number)
October 31
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Date of Fiscal Year End
April 30, 2004
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Date of Reporting Period
<Page>
ITEM 1. REPORTS TO STOCKHOLDERS
<Page>
TAX-MANAGED MID-CAP CORE PORTFOLIO as of April 30, 2004
PORTFOLIO OF INVESTMENTS (Unaudited)
COMMON STOCKS -- 99.3%
<Table>
<Caption>
SECURITY SHARES VALUE
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ADVERTISING AGENCIES -- 2.3%
Omnicom Group, Inc. 17,500 $ 1,391,425
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$ 1,391,425
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AIRLINES -- 1.0%
SkyWest, Inc. 31,200 $ 567,840
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$ 567,840
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BANKS - REGIONAL -- 2.3%
City National Corp. 11,500 $ 708,975
SouthTrust Corp. 21,600 671,328
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$ 1,380,303
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BROADCASTING AND RADIO -- 1.5%
Cox Radio, Inc. Class A(1) 42,100 $ 871,891
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$ 871,891
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BUILDING PRODUCTS -- 1.8%
Valspar Corp. 21,900 $ 1,087,335
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$ 1,087,335
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BUSINESS SERVICES - MISCELLANEOUS -- 5.9%
ChoicePoint, Inc.(1) 28,966 $ 1,272,187
Fiserv, Inc.(1) 27,400 1,001,744
SEI Investments Co. 20,100 593,352
The Reynolds and Reynolds Co., Class A 22,700 648,312
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$ 3,515,595
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CHEMICALS -- 1.4%
Air Products and Chemicals, Inc. 16,800 $ 836,808
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$ 836,808
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COMPUTER SERVICES -- 2.1%
BEA Systems, Inc.(1) 44,600 $ 508,886
SunGard Data Systems, Inc.(1) 27,200 709,104
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$ 1,217,990
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COMPUTER SOFTWARE -- 0.7%
National Instruments Corp. 14,050 $ 429,368
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$ 429,368
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COMPUTERS - INTEGRATED SYSTEMS -- 1.2%
Jack Henry & Associates, Inc. Class A 38,900 $ 707,591
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$ 707,591
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COSMETICS & TOILETRIES -- 2.1%
Alberto-Culver Co. 25,950 $ 1,223,802
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$ 1,223,802
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DISTRIBUTION/WHOLESALE -- 2.0%
CDW Corp. 18,600 $ 1,162,314
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$ 1,162,314
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EDUCATION -- 1.3%
Education Management Corp.(1) 21,000 $ 744,660
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$ 744,660
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ELECTRICAL EQUIPMENT -- 1.5%
Cooper Industries Ltd. Class A 16,500 $ 906,015
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$ 906,015
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ELECTRONICS - EQUIPMENT / INSTRUMENTS -- 2.1%
Amphenol Corp. Class A(1) 39,900 $ 1,261,239
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$ 1,261,239
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ELECTRONICS - SEMICONDUCTORS -- 1.4%
QLogic Corp.(1) 30,900 $ 833,991
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$ 833,991
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ENGINEERING AND CONSTRUCTION -- 1.4%
Jacobs Engineering Group, Inc.(1) 20,400 $ 850,884
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$ 850,884
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</Table>
See notes to financial statements
12
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<Table>
<Caption>
SECURITY SHARES VALUE
- ----------------------------------------------------------------------------------------------
FINANCE - INVESTMENT MANAGEMENT -- 6.1%
Affiliated Managers Group, Inc.(1) 19,500 $ 949,650
Ambac Financial Group, Inc. 9,400 648,600
Franklin Resources, Inc. 17,700 970,491
Legg Mason, Inc. 11,600 1,067,896
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$ 3,636,637
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FOOD - WHOLESALE / DISTRIBUTION -- 3.1%
Dean Foods Co.(1) 16,200 $ 543,996
Performance Food Group Co.(1) 36,800 1,292,784
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$ 1,836,780
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GAS DISTRIBUTION -- 1.2%
Piedmont Natural Gas Co., Inc. 16,900 $ 684,450
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$ 684,450
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HEALTHCARE SERVICES -- 1.0%
Express Scripts, Inc.(1) 7,700 $ 595,518
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$ 595,518
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HOUSEHOLD PRODUCTS -- 2.0%
Mohawk Industries, Inc.(1) 15,300 $ 1,180,242
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$ 1,180,242
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INSURANCE -- 3.9%
Ace Ltd. 32,200 $ 1,411,648
Nationwide Financial Services, Inc., Class A 25,900 890,960
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$ 2,302,608
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INSURANCE BROKERS -- 1.1%
Arthur J. Gallagher & Co., Inc. 19,600 $ 631,708
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$ 631,708
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INVESTMENT SERVICES -- 1.2%
A.G. Edwards, Inc. 20,000 $ 731,800
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$ 731,800
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MANUFACTURING -- 3.7%
Dover Corp. 15,500 $ 620,465
Engineered Support Systems, Inc. 11,800 573,834
Pentair, Inc. 16,600 989,194
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$ 2,183,493
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MEDICAL - HOSPITALS -- 2.8%
Health Management Associates, Inc. Class A 72,700 $ 1,681,551
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$ 1,681,551
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MEDICAL DEVICES -- 2.1%
Varian Medical Systems, Inc.(1) 14,300 $ 1,227,512
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$ 1,227,512
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MEDICAL PRODUCTS -- 6.3%
Biomet, Inc. 30,600 $ 1,208,700
C.R. Bard, Inc. 6,600 701,382
Patterson Dental Co.(1) 13,900 1,024,430
Renal Care Group, Inc.(1) 16,500 816,420
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$ 3,750,932
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MEDICAL SERVICES / SUPPLIES -- 2.4%
DENTSPLY International, Inc. 29,400 $ 1,424,724
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$ 1,424,724
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MULTI-UTILITIES -- 1.6%
Questar Corp. 26,700 $ 947,049
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$ 947,049
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OFFICE ELECTRONICS / TECHNOLOGY -- 1.5%
Zebra Technologies Corp. Class A(1) 12,150 $ 890,473
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$ 890,473
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OIL AND GAS - EXPLORATION AND PRODUCTION -- 7.6%
Apache Corp. 22,550 $ 944,169
EOG Resources, Inc. 19,900 980,075
Newfield Exploration Co.(1) 28,700 1,511,916
Pogo Producing Co. 22,200 1,094,904
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$ 4,531,064
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</Table>
See notes to financial statements
13
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<Table>
<Caption>
SECURITY SHARES VALUE
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PERSONAL PRODUCTS -- 1.3%
Estee Lauder Cos., Inc. (The), Class A 17,300 $ 790,783
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$ 790,783
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PRINTING AND BUSINESS PRODUCTS -- 1.7%
Avery Dennison Corp. 15,500 $ 995,565
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$ 995,565
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PUBLISHING -- 1.8%
E.W. Scripps Co. 10,200 $ 1,076,610
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$ 1,076,610
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RETAIL - DISCOUNT -- 2.5%
99 Cents Only Stores(1) 34,500 $ 681,720
Family Dollar Stores, Inc. 24,000 771,360
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$ 1,453,080
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RETAIL - RESTAURANTS -- 3.5%
Brinker International, Inc.(1) 30,000 $ 1,153,800
Sonic Corp.(1) 28,400 916,468
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$ 2,070,268
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RETAIL - SPECIALTY AND APPAREL -- 1.4%
Bed Bath and Beyond, Inc.(1) 22,500 $ 835,200
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$ 835,200
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SEMICONDUCTORS & SEMICONDUCTOR EQUIPMENT -- 1.0%
Microchip Technology, Inc. 21,750 $ 609,435
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$ 609,435
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SPECIALTY CHEMICALS AND MATERIALS -- 1.6%
Ecolab, Inc. 31,500 $ 938,700
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$ 938,700
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TELECOMMUNICATIONS -- 1.2%
CenturyTel, Inc. 24,700 $ 713,336
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$ 713,336
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TRANSPORTATION -- 3.7%
C.H. Robinson Worldwide, Inc. 27,900 $ 1,145,016
Expeditors International of Washington, Inc. 26,100 1,048,959
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$ 2,193,975
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TOTAL COMMON STOCKS
(IDENTIFIED COST $50,758,880) $ 58,902,544
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TOTAL INVESTMENTS -- 99.3%
(IDENTIFIED COST $50,758,880) $ 58,902,544
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OTHER ASSETS, LESS LIABILITIES -- 0.7% $ 427,464
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NET ASSETS -- 100.0% $ 59,330,008
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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, 2004
FINANCIAL STATEMENTS (UNAUDITED)
STATEMENT OF ASSETS AND LIABILITIES
AS OF APRIL 30, 2004
<Table>
ASSETS
Investments, at value (identified cost, $50,758,880) $ 58,902,544
Cash 445,077
Receivable for investments sold 591,887
Dividends and interest receivable 14,125
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TOTAL ASSETS $ 59,953,633
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LIABILITIES
Payable for investments purchased $ 604,288
Payable to affiliate for Trustees' fees 143
Accrued expenses 19,194
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TOTAL LIABILITIES $ 623,625
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NET ASSETS APPLICABLE TO INVESTORS' INTEREST IN PORTFOLIO $ 59,330,008
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SOURCES OF NET ASSETS
Net proceeds from capital contributions and withdrawals $ 51,186,344
Net unrealized appreciation (computed on the basis of identified cost) 8,143,664
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TOTAL $ 59,330,008
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</Table>
STATEMENT OF OPERATIONS
FOR THE SIX MONTHS ENDED
APRIL 30, 2004
<Table>
INVESTMENT INCOME
Dividends $ 195,292
Interest 1,573
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TOTAL INVESTMENT INCOME $ 196,865
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EXPENSES
Investment adviser fee $ 218,931
Trustees' fees and expenses 951
Custodian fee 23,886
Legal and accounting services 7,914
Miscellaneous 1,273
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TOTAL EXPENSES $ 252,955
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NET INVESTMENT LOSS $ (56,090)
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REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) --
Investment transactions (identified cost basis) $ 1,349,685
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NET REALIZED GAIN $ 1,349,685
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Change in unrealized appreciation (depreciation) --
Investments (identified cost basis) $ 1,242,755
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NET CHANGE IN UNREALIZED APPRECIATION (DEPRECIATION) $ 1,242,755
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NET REALIZED AND UNREALIZED GAIN $ 2,592,440
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NET INCREASE IN NET ASSETS FROM OPERATIONS $ 2,536,350
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</Table>
See notes to financial statements
15
<Page>
STATEMENTS OF CHANGES IN NET ASSETS
<Table>
<Caption>
SIX MONTHS ENDED
INCREASE (DECREASE) APRIL 30, 2004 YEAR ENDED
IN NET ASSETS (UNAUDITED) OCTOBER 31, 2003
- --------------------------------------------------------------------------------------
From operations --
Net investment loss $ (56,090) $ (64,901)
Net realized gain (loss) from
investments 1,349,685 (927,356)
Net change in unrealized
appreciation (depreciation) of
investments 1,242,755 8,290,032
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NET INCREASE IN NET ASSETS FROM OPERATIONS $ 2,536,350 $ 7,297,775
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Capital transactions --
Contributions $ 12,224,040 $ 25,984,940
Withdrawals (1,542,653) (4,319,456)
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NET INCREASE IN NET ASSETS FROM
CAPITAL TRANSACTIONS $ 10,681,387 $ 21,665,484
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NET INCREASE IN NET ASSETS $ 13,217,737 $ 28,963,259
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NET ASSETS
At beginning of period $ 46,112,271 $ 17,149,012
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AT END OF PERIOD $ 59,330,008 $ 46,112,271
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</Table>
See notes to financial statements
16
<Page>
SUPPLEMENTARY DATA
<Table>
<Caption>
SIX MONTHS ENDED YEAR ENDED OCTOBER 31,
APRIL 30, 2004 ----------------------------------
(UNAUDITED) 2003 2002(1)
- ---------------------------------------------------------------------------------------------------------------------
RATIOS/SUPPLEMENTAL DATA
Ratios (As a percentage of average daily net assets):
Expenses 0.93%(2) 0.99% 1.68%(2)
Net investment loss (0.21)%(2) (0.22)% (0.81)%(2)
Portfolio Turnover 18% 50% 13%
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TOTAL RETURN(3) 5.08% 25.97% (14.72)%
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NET ASSETS, END OF PERIOD (000'S OMITTED) $ 59,330 $ 46,112 $ 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
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TAX-MANAGED MID-CAP CORE PORTFOLIO as of April 30, 2004
NOTES TO FINANCIAL STATEMENTS (UNAUDITED)
1 SIGNIFICANT ACCOUNTING POLICIES
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, 2004, the Eaton
Vance Tax-Managed Mid-Cap Core Fund held an approximate 33.2% interest in the
Portfolio and one other investor owned an interest greater than 10% that
equaled 66.6%. 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 -- Securities listed on a U.S. securities exchange
generally are valued at the last sale price on the day of valuation or, if no
sales took place on such date, at the mean between the closing bid and asked
prices therefore on the exchange where such securities are principally
traded. Equity securities listed on NASDAQ National Market System generally
are valued at the official NASDAQ closing price. Unlisted or listed
securities for which closing sales prices or closing quotations are not
available are valued at the mean between the latest available bid and asked
prices. Exchange-traded options are valued at the last sale price for the day
of valuation as quoted on the principal exchange or board of trade on which
the options are traded or, in the absence of sales on such date, at the mean
between the latest bid and asked prices therefore. Futures positions on
securities and currencies generally are valued at closing settlement prices.
Short-term debt securities with a remaining maturity of 60 days or less are
valued at amortized cost. If short-term debt securities were acquired with a
remaining maturity of more than 60 days, their amortized cost value will be
based on their value on the sixty-first day prior to maturity. 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. The daily valuation of foreign
securities generally is determined as of the close of trading on the
principal exchange on which such securities trade. Events occurring after the
close of trading on foreign exchanges may result in adjustments to the
valuation of foreign securities to more accurately reflect their fair value
as of the close of regular trading on the New York Stock Exchange.
The Portfolio may rely on an independent fair valuation service in adjusting
the valuations of foreign securities. Foreign securities and currencies are
valued in U.S. dollars, based on foreign currency exchange rate quotations
supplied by an independent quotation service. Investments held by the
Portfolio 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 of the Portfolio considering relevant factors, data
and information including the market value of freely tradable securities of
the same class in the principal market on which such securities are normally
traded.
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.
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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 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 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.
I OTHER -- Investment transactions are accounted for on a trade date basis.
J INDEMNIFICATIONS -- Under the Portfolio's organizational documents, its
officers and Trustees may be indemnified against certain liabilities and
expenses arising out of the performance of their duties to the Portfolio.
Interestholders in the Portfolio are jointly and severally liable for the
liabilities and obligations of the Portfolio in the event that the Portfolio
fails to satisfy such liabilities and obligations; provided, however, that,
to the extent assets are available in the Portfolio, the Portfolio may, under
certain circumstances, indemnify interestholders from and against any claim
or liability to which such holder may become subject by reason of being or
having been an interestholder in the Portfolio. Additionally, in the normal
course of business, the Portfolio enters into agreements with service
providers that may contain indemnification clauses. The Portfolio's maximum
exposure under these arrangements is unknown as this would involve future
claims that may be made against the Portfolio that have not yet occurred.
K INTERIM FINANCIAL STATEMENTS - The interim financial statements relating to
April 30, 2004 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 or 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, 2004, the advisory fee amounted to $218,931.
Pursuant to a sub-advisory agreement, BMR has delegated the investment
management of the Portfolio to Atlanta Capital Management Company, LLC
(Atlanta Capital), a
19
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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, 2004, 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 $21,104,961 and $9,645,859, respectively, for the six months ended
April 30, 2004.
4 FEDERAL INCOME TAX BASIS OF UNREALIZED APPRECIATION (DEPRECIATION)
The cost and unrealized appreciation (depreciation) in value of the
investments owned at April 30, 2004, as computed on a federal income tax
basis, were as follows:
<Table>
AGGREGATE COST $ 50,758,880
--------------------------------------------------------------
Gross unrealized appreciation $ 8,988,023
Gross unrealized depreciation (844,359)
--------------------------------------------------------------
NET UNREALIZED APPRECIATION $ 8,143,664
--------------------------------------------------------------
</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, 2004.
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, 2004.
20
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EATON VANCE TAX-MANAGED MID-CAP CORE FUND
INVESTMENT MANAGEMENT
EATON VANCE TAX-MANAGED MID-CAP CORE FUND
OFFICERS
Thomas E. Faust Jr.
President
William H. Ahern, Jr.
Vice President
Thomas J. Fetter
Vice President
Michael R. Mach
Vice President
Robert B. MacIntosh
Vice President
Duncan W. Richardson
Vice President
Walter A. Row, III
Vice President
Judith A. Saryan
Vice President
Susan Schiff
Vice President
James L. O'Connor
Treasurer
Alan R. Dynner
Secretary
TRUSTEES
James B. Hawkes
Samuel L. Hayes, III
William H. Park
Ronald A. Pearlman
Norton H. Reamer
Lynn A. Stout
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
Samuel L. Hayes, III
William H. Park
Ronald A. Pearlman
Norton H. Reamer
Lynn A. Stout
21
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ITEM 2. CODE OF ETHICS
The registrant has adopted a code of ethics applicable to its Principal
Executive Officer, Principal Financial Officer and Principal Accounting Officer.
The registrant undertakes to provide a copy of such code of ethics to any person
upon request, without charge, by calling 1-800-262-1122.
ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT
The registrant's Board has designated William H. Park, Samuel L. Hayes, III and
Norton H. Reamer, each an independent trustee, as its audit committee financial
experts. Mr. Park is a certified public accountant who is the President and
Chief Executive Officer of Prizm Capital Management, LLC (investment management
firm). Previously, he served as Executive Vice President and Chief Financial
Officer of United Asset Management Corporation ("UAM") (a holding company owning
institutional investment management firms). Mr. Hayes is the Jacob H. Schiff
Professor of Investment Banking Emeritus of the Harvard University Graduate
School of Business Administration. Mr. Reamer is the President, Chief Executive
Officer and a Director of Asset Management Finance Corp. (a specialty finance
company serving the investment management industry) and is President of Unicorn
Corporation (an investment and financial advisory services company). Formerly,
Mr. Reamer was Chairman of Hellman, Jordan Management Co., Inc. (an investment
management company) and Advisory Director of Berkshire Capital Corporation (an
investment banking firm), Chairman of the Board of UAM and Chairman, President
and Director of the UAM Funds (mutual funds).
ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES
Not required in this filing.
ITEM 5. AUDIT COMMITTEE OF LISTED REGISTRANTS
Not required in this filing.
ITEM 6. SCHEDULE OF INVESTMENTS
Please see schedule of investments contained in the Report to Stockholders
included under Item 1 of this Form N-CSR.
ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END
MANAGEMENT INVESTMENT COMPANIES
Not required in this filing.
ITEM 8. PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT
COMPANY AND AFFILIATED PURCHASERS.
Not required in this filing.
ITEM 9. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.
Effective February 9, 2004, the Governance Committee of the Board of Trustees
formalized the procedures by which a Fund's shareholders may recommend nominees
to the registrant's Board of Trustees. The Governance Committee shall, when
identifying candidates for the position of Independent Trustee, consider any
such candidate recommended by a shareholder of a Fund if such recommendation
contains sufficient background information concerning the candidate, and is
received in a sufficiently timely manner (and in any event no later than the
date specified for receipt of shareholder proposals in any applicable proxy
statement with respect to a Fund). Shareholders shall be
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directed to address any such recommendations to the attention of the Governance
Committee, c/o the Secretary of the Fund.
ITEM 10. 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 changes in the registrant's internal controls over
financial reporting during the period that has materially affected, or is
reasonably likely to materially affect the registrant's internal control over
financial reporting.
ITEM 11. EXHIBITS
(a)(1) Registrant's Code of Ethics - Not applicable (please see Item 2).
(a)(2)(i) Treasurer's Section 302 certification.
(a)(2)(ii) President's Section 302 certification.
(b) Combined Section 906 certification.
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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 17, 2004
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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
-------------------------
Michelle A. Alexander
Treasurer
Date: June 17, 2004
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By: /S/ James B. Hawkes
-------------------
James B. Hawkes
President
Date: June 17, 2004
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