NBD Nuveen Build America Bond Opportunity Fund of Beneficial Interest (delisted)

000 A000000 09/30/2012
000 C000000 0001493523
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 6.1
000 J000000 A
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002 A000000 333 WEST WACKER DRIVE
002 B000000 CHICAGO
002 C000000 IL
002 D010000 60606
002 D020000 1286
003  000000 N
004  000000 N
005  000000 N
006  000000 N
007 A000000 N
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007 C010800  8
007 C010900  9
007 C011000 10
008 A000001 NUVEEN FUND ADVISORS, INC.
008 B000001 A
008 C000001 801-801-17
008 D010001 CHICAGO
008 D020001 IL
008 D030001 60606
008 D040001 1286
008 A000002 NUVEEN ASSET MANAGEMENT, LLC
008 B000002 S
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008 D020002 IL
008 D030002 60606
008 D040002 1286
012 A000001 COMPUTERSHARE
012 B000001 84-05925
012 C010001 PROVIDENCE
012 C020001 RI

012 C030001 02940
013 A000001 ERNST & YOUNG LLP
013 B010001 CHICAGO
013 B020001 IL
013 B030001 60606
014 A000001 NUVEEN INVESTMENTS, LLC
014 B000001 8-13464
015 A000001 STATE STREET BANK AND TRUST COMPANY
015 B000001 C
015 C010001 BOSTON
015 C020001 MA
015 C030001 02110
015 E010001 X
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019 C000000 NUVEENFUND
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022 B000006 41-0953246
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022 D000006       968
022 A000007 FMS BONDS INC
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022 A000008 LOOP CAPITAL MARKETS
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022 A000009 STERN BROTHERS & CO
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022 A000010 THE MUNI CENTER INC
022 B000010 06-1585654
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087 A020000 67074C103
087 A030000 NBD
088 A000000 N
088 B000000 N
088 C000000 N
088 D000000 N

SIGNATURE   STEPHEN D. FOY
TITLE       V.P. & CONTROLLER