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EXHIBIT 77(O) MORGAN STANLEY DEAN WITTER DEVELOPING SECURITIES TRUST
10f-3 transactions for the period December 31, 1999- March 31, 2000
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S
TOTAL
ISSUED/
DATE PRICE SHARES % of PRINCIPAL PURCHASED
SECURITY PURCHASED SHARE PURCHASED Assets AMOUNT BY FUND BROKER(S)
Aether Systems 10/20/99 $ 16.00 14,500 0.029% $ 96,000,000.00 0.242% Merrill Lynch
Aclara Biosciences 03/20/00 $ 21.00 23,800 0.039% $ 189,000,000.00 0.264% Deutsche Banc
Agilent Technologies 11/17/99 $ 30.00 80,100 0.250% $ 2,160,000,000.00 0.111% Hambrecht & Quist
Antgenic 02/04/00 $ 18.00 9,300 0.013% $ 63,000,000.00 0.013% Piper Jaffray
Asiainfo 03/03/00 $ 24.00 4,000 0.005% $ 120,000,000.00 0.080% Deutsche Banc
Aspect Medical Systems 01/27/00 $ 15.00 16,500 0.019% $ 52,500,000.00 0.471% Piper Jaffray
Breakaway Solutions 10/05/99 $ 14.00 12,800 0.022% $ 42,000,000.00 0.427% Dain Rauscher
Cacheflow Inc. 11/18/99 $ 24.00 5,300 0.012% $ 120,000,000.00 0.106% Goldman Sachs
Charter Communications 11/08/99 $ 19.00 115,000 0.227% $ 3,230,000,000.00 0.068% Goldman Sachs
Digitas 03/14/00 $ 24.00 24,700 0.038% $ 223,200,000.00 0.266% SG Cowen
Diversa 02/14/00 $ 24.00 32,500 0.054% $ 174,000,000.00 0.448% Bear Stearns
Eloquent 02/16/00 $ 16.00 16,100 0.017% $ 72,000,000.00 0.358% Piper Jaffray
Expedior Inc. 12/15/99 $ 19.00 8,400 0.014% $ 162,165,000.00 0.098% DLJ
Expedia Inc. 11/09/99 $ 14.00 25,600 0.037% $ 72,800,000.00 0.492% Goldman Sachs
First World 03/07/00 $ 17.00 41,900 0.041% $ 170,000,000.00 0.419% Lehman Brothers
GT Group Telecom 03/09/00 $ 14.00 45,100 0.033% $ 252,000,000.00 0.251% Salomon Brothers
HomeGrocer.com 03/09/00 $ 12.00 18,500 0.012% $ 264,000,000.00 0.084% McDonald & Co.
Illuminet 10/07/99 $ 19.00 17,800 0.041% $ 74,100,000.00 0.456% BancBoston
Immersion Corp. 11/12/99 $ 12.00 17,800 0.022% $ 51,000,000.00 0.419% Hambrecht & Quist
Information Holdings Inc. 03/14/00 $ 36.50 182,000 0.347% $ 164,250,000.00 4.044% Deutsche Banc
Intertrust Technologies 10/26/99 $ 18.00 45,500 0.099% $ 117,000,000.00 0.700% Credit Suisse
Martha Stewart Living 10/18/99 $ 18.00 15,500 0.036% $ 129,600,000.00 0.215% DLJ
McAfee.com 12/01/99 $ 12.00 25,100 0.028% $ 75,000,000.00 0.402% Thomas Weisel
MCK Communications 10/22/99 $ 16.00 31,400 0.060% $ 54,400,000.00 0.924% BancRobertson
Metasolv Software 11/17/99 $ 19.00 3,300 0.006% $ 95,000,000.00 0.066% Soundview
NDS/NNDS 11/22/99 $ 20.00 36,000 0.069% $ 180,000,000.00 0.400% Merrill Lynch
Palm Inc. 03/01/00 $ 38.00 19,350 0.042% $ 874,000,000.00 0.084% BancAmerica
Quantum Effect Devices 01/31/00 $ 16.00 8,900 0.011% $ 59,520,000.00 0.239% Wasserstein Perella
Radio Unica Communications 10/19/99 $ 16.00 33,200 0.068% $ 109,440,000.00 0.485% Salomon Smith Barney
Regent Communications 01/25/00 $ 8.50 99,800 0.067% $ 136,000,000.00 0.624% Prudential Securities
Sequenom 01/31/00 $ 26.00 22,200 0.047% $ 136,500,000.00 0.423% Warburg Dillon
Silicon Laboratories 03/23/00 $ 31.00 10,000 0.022% $ 99,200,000.00 0.313% Lehman Brothers
Spanish Broadcasting 10/27/99 $ 20.00 74,600 0.181% $ 435,748,000.00 0.342% Lehman Brothers
Spectrasite Holdings 02/01/00 $ 17.00 185,000 0.253% $ 379,100,000.00 0.830% Tucker Anthony
Therma Wave 02/03/00 $ 20.00 46,300 0.073% $ 180,000,000.00 0.514% Banc of America
Tularik Inc. 12/09/99 $ 14.00 50,500 0.062% $ 97,300,000.00 0.727% Lehman Brothers
Webmethods 02/10/00 $ 35.000 4,800 0.012% $ 143,500,000.00 0.117% Dain Rauscher
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