PAGE 1 000 B000000 11/30/2003 000 C000000 0001190935 000 D000000 N 000 E000000 NF 000 F000000 Y 000 G000000 N 000 H000000 N 000 I000000 6.1 000 J000000 A 001 A000000 PIMCO CORPORATE OPPORTUNITY FUND 001 B000000 811-21238 001 C000000 2127393371 002 A000000 1345 AVENUE OF THE AMERICAS 002 B000000 NEW YORK 002 C000000 NY 002 D010000 10105 003 000000 N 004 000000 N 005 000000 N 006 000000 N 007 A000000 N 007 B000000 0 007 C010100 1 007 C010200 2 007 C010300 3 007 C010400 4 007 C010500 5 007 C010600 6 007 C010700 7 007 C010800 8 007 C010900 9 007 C011000 10 008 A000001 PIMCO ADVISORS FUND MANAGEMENT LLC 008 B000001 A 008 C000001 801-31227 008 D010001 NEW YORK 008 D020001 NY 008 D030001 10105 008 A000002 PACIFIC INVESTMENT MANAGEMENT COMPANY LLC 008 B000002 S 008 C000002 801-48187 008 D010002 NEWPORT BEACH 008 D020002 CA 008 D030002 92660 011 A000001 MERRILL LYNCH PIERCE FENNER & SMITH 011 B000001 8-07221 011 C010001 NEW YORK 011 C020001 NY 011 C030001 10080 011 A000002 AG EDWARDS & SONS INC. 011 B000002 8-03548 PAGE 2 011 C010002 ST. LOUIS 011 C020002 MO 011 C030002 63103 011 A000003 PRUDENTIAL SECURITIES INC. 011 B000003 8-04060 011 C010003 NEW YORK 011 C020003 NY 011 C030003 10080 011 A000004 UBS WARBURG LLC 011 B000004 8-22651 011 C010004 STAMFORD 011 C020004 CT 011 C030004 06901 011 A000005 RBC DAIN RAUSCHER INC. 011 B000005 8-45411 011 C010005 MINNEAPOLIS 011 C020005 MN 011 C030005 55402 011 A000006 WACHOVIA SECURITIES INC. 011 B000006 8-02612 011 C010006 CHARLOTTE 011 C020006 NC 011 C030006 28202 011 A000007 ADVEST, INC. 011 B000007 8-04159 011 C010007 HARTFORD 011 C020007 CT 011 C030007 06103 012 A000001 PFPC INC. 012 B000001 84-58023 012 C010001 PROVIDENCE 012 C020001 RI 012 C030001 02940 013 A000001 PRICEWATERHOUSECOOPERS LLP 013 B010001 NEW YORK 013 B020001 NY 013 B030001 10036 014 A000001 DRESDNER BANK AG 014 B000001 8-12859 014 A000002 DRESDNER KLENWORT WASSERSTEIN SECURITIES LLC 014 B000002 8-49647 014 A000003 DRESDNER KLENWORT BENSON 014 B000003 8-00000 014 A000004 GRANCHESTER SECURITIES 014 B000004 8-00000 015 A000001 STATE STREET CORP. 015 B000001 C 015 C010001 KANSAS CITY 015 C020001 MO 015 C030001 64105 015 E010001 X PAGE 3 018 000000 Y 019 A000000 Y 019 B000000 18 019 C000000 PIMCOADVIS 020 A000001 DEUTSCHE BANK CLEARING SERVICES 020 B000001 13-2730828 020 C000001 18 020 A000002 MERRILL LYNCH PIERCE FENNER & SMITH 020 B000002 13-5674085 020 C000002 10 020 A000003 GOLDMAN SACHS 020 B000003 13-5108880 020 C000003 9 020 A000004 CITIGROUP GLOBAL MARKETS INC. 020 B000004 52-1568099 020 C000004 4 020 A000005 LEHMAN BROTHERS SECURITIES 020 B000005 13-2418466 020 C000005 4 020 A000006 TORONTO DOMINION SECURITIES 020 B000006 22-2203727 020 C000006 2 020 A000007 MORGAN STANLEY CO. 020 B000007 13-2655998 020 C000007 2 020 A000008 CREDIT SUISSE FIRST BOSTON 020 B000008 13-5650485 020 C000008 2 020 A000009 JP MORGAN CHASE SECURITIES 020 B000009 13-3112953 020 C000009 1 020 C000010 0 021 000000 52 022 A000001 LEHMAN BROTHERS SECURITES 022 B000001 13-2418466 022 C000001 4196012 022 D000001 55603 022 A000002 CREDIT SUISSE FIRST BOSTON 022 B000002 13-5659485 022 C000002 2937668 022 D000002 47626 022 A000003 STATE STREET BANK TRUST 022 B000003 04-2456637 022 C000003 2598507 022 D000003 0 022 A000004 BANC OF AMERICA SECURITIES 022 B000004 94-1687665 022 C000004 351232 022 D000004 375750 022 A000005 MORGAN STANLEY CO. 022 B000005 13-2655998 PAGE 4 022 C000005 443853 022 D000005 186107 022 A000006 CITIGROUP GLOBAL MARKETS 022 B000006 52-1568099 022 C000006 498164 022 D000006 33382 022 A000007 GOLDMAN SACHS 022 B000007 13-5108880 022 C000007 289786 022 D000007 180790 022 A000008 JP MORGAN CHASE SECURITIES 022 B000008 13-3112953 022 C000008 275585 022 D000008 91406 022 A000009 UBS WARBURG 022 B000009 13-2932996 022 C000009 247620 022 D000009 74724 022 A000010 MERRILL LYNCH PIERCE FENNER & SMITH 022 B000010 13-5674085 022 C000010 145763 022 D000010 115392 023 C000000 12293899 023 D000000 1223032 024 000000 N 025 D000001 0 025 D000002 0 025 D000003 0 025 D000004 0 025 D000005 0 025 D000006 0 025 D000007 0 025 D000008 0 026 A000000 N 026 B000000 N 026 C000000 N 026 D000000 Y 026 E000000 N 026 F000000 N 026 G010000 N 026 G020000 N 026 H000000 N 027 000000 N 028 A010000 0 028 A020000 0 028 A030000 0 028 A040000 0 028 B010000 0 028 B020000 0 028 B030000 0 028 B040000 0 PAGE 5 028 C010000 0 028 C020000 0 028 C030000 0 028 C040000 0 028 D010000 0 028 D020000 0 028 D030000 0 028 D040000 0 028 E010000 0 028 E020000 0 028 E030000 0 028 E040000 0 028 F010000 0 028 F020000 0 028 F030000 0 028 F040000 0 028 G010000 0 028 G020000 0 028 G030000 0 028 G040000 0 028 H000000 0 030 A000000 0 030 B000000 0.00 030 C000000 0.00 031 A000000 0 031 B000000 0 032 000000 0 033 000000 0 035 000000 0 036 B000000 0 038 000000 0 042 A000000 0 042 B000000 0 042 C000000 0 042 D000000 0 042 E000000 0 042 F000000 0 042 G000000 0 042 H000000 0 043 000000 0 044 000000 0 045 000000 Y 046 000000 N 047 000000 Y 048 000000 0.600 048 A010000 0 048 A020000 0.000 048 B010000 0 048 B020000 0.000 048 C010000 0 048 C020000 0.000 PAGE 6 048 D010000 0 048 D020000 0.000 048 E010000 0 048 E020000 0.000 048 F010000 0 048 F020000 0.000 048 G010000 0 048 G020000 0.000 048 H010000 0 048 H020000 0.000 048 I010000 0 048 I020000 0.000 048 J010000 0 048 J020000 0.000 048 K010000 0 048 K020000 0.000 049 000000 N 050 000000 N 051 000000 N 052 000000 N 053 A000000 N 054 A000000 Y 054 B000000 Y 054 C000000 N 054 D000000 N 054 E000000 N 054 F000000 N 054 G000000 Y 054 H000000 Y 054 I000000 N 054 J000000 Y 054 K000000 N 054 L000000 N 054 M000000 Y 054 N000000 N 054 O000000 N 055 A000000 N 055 B000000 N 056 000000 Y 057 000000 N 058 A000000 N 059 000000 Y 060 A000000 Y 060 B000000 Y 061 000000 0 062 A000000 Y 062 B000000 0.0 062 C000000 0.3 062 D000000 0.3 062 E000000 0.0 062 F000000 0.0 PAGE 7 062 G000000 0.0 062 H000000 0.0 062 I000000 9.8 062 J000000 0.0 062 K000000 -0.1 062 L000000 0.0 062 M000000 0.0 062 N000000 3.3 062 O000000 0.0 062 P000000 81.1 062 Q000000 6.3 062 R000000 0.0 063 A000000 0 063 B000000 9.7 064 A000000 N 064 B000000 Y 065 000000 N 066 A000000 N 067 000000 N 068 A000000 N 068 B000000 N 069 000000 N 070 A010000 Y 070 A020000 Y 070 B010000 N 070 B020000 N 070 C010000 Y 070 C020000 Y 070 D010000 Y 070 D020000 N 070 E010000 Y 070 E020000 Y 070 F010000 Y 070 F020000 N 070 G010000 Y 070 G020000 Y 070 H010000 Y 070 H020000 N 070 I010000 N 070 I020000 N 070 J010000 Y 070 J020000 Y 070 K010000 Y 070 K020000 N 070 L010000 Y 070 L020000 Y 070 M010000 Y 070 M020000 Y 070 N010000 Y 070 N020000 N 070 O010000 Y PAGE 8 070 O020000 N 070 P010000 Y 070 P020000 N 070 Q010000 N 070 Q020000 N 070 R010000 Y 070 R020000 N 071 A000000 1811928 071 B000000 357716 071 C000000 1371117 071 D000000 26 072 A000000 11 072 B000000 113333 072 C000000 0 072 D000000 0 072 E000000 0 072 F000000 8160 072 G000000 0 072 H000000 0 072 I000000 25 072 J000000 314 072 K000000 0 072 L000000 72 072 M000000 43 072 N000000 0 072 O000000 6 072 P000000 0 072 Q000000 0 072 R000000 51 072 S000000 29 072 T000000 0 072 U000000 0 072 V000000 0 072 W000000 1228 072 X000000 9928 072 Y000000 38 072 Z000000 103443 072AA000000 14769 072BB000000 0 072CC010000 157135 072CC020000 0 072DD010000 92743 072DD020000 0 072EE000000 0 073 A010000 1.4552 073 A020000 0.0000 073 B000000 0.0000 073 C000000 0.0000 074 A000000 1948 074 B000000 4875 074 C000000 166695 PAGE 9 074 D000000 1500649 074 E000000 0 074 F000000 0 074 G000000 0 074 H000000 0 074 I000000 0 074 J000000 2261 074 K000000 0 074 L000000 30535 074 M000000 148 074 N000000 1707111 074 O000000 38841 074 P000000 812 074 Q000000 0 074 R010000 0 074 R020000 0 074 R030000 999 074 R040000 13031 074 S000000 565000 074 T000000 1088428 074 U010000 63730 074 U020000 0 074 V010000 17.08 074 V020000 0.00 074 W000000 0.0000 074 X000000 95 074 Y000000 0 075 A000000 0 075 B000000 1464318 076 000000 16.88 077 A000000 Y 077 B000000 Y 078 000000 N 080 A000000 ICI MUTUAL INSURANCE COMPANY 080 C000000 23000 081 A000000 Y 081 B000000 28 082 A000000 N 082 B000000 0 083 A000000 N 083 B000000 0 084 A000000 N 084 B000000 0 085 A000000 Y 085 B000000 N 086 A010000 63230 086 A020000 905770 086 B010000 0 086 B020000 0 086 C010000 23 086 C020000 565000 PAGE 10 086 D010000 0 086 D020000 0 086 E010000 0 086 E020000 0 086 F010000 0 086 F020000 0 087 A010000 COMMON 087 A020000 72201B101 087 A030000 PTY 087 B010000 PREFERRED 087 B020000 72201B200 087 B030000 SERIES A 088 A000000 N 088 B000000 N 088 C000000 N 088 D000000 Y SIGNATURE LARRY ALTADONNA TITLE TREASURER