Nuveen Municipal Opportunity Fund Form 3 Initial statement of insider ownership

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

CITIGROUP INC

(Last) (First) (Middle)

388 GREENWICH STREET

(Street)

NEW YORK NY 10013

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
02/23/2016

3. Issuer Name and Ticker or Trading Symbol
NUVEEN MUNICIPAL OPPORTUNITY FUND INC [ NIO ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Variable Rate Demand Preferred Shares	850	I	By Subsidiary(1)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The Variable Rate Demand Preferred Shares ("Shares") reported in Table I represent Shares beneficially owned by Citigroup Global Markets Inc. ("CGMI"). Citigroup Financial Products Inc. ("CFP") is the sole stockholder of CGMI. Citigroup Global Markets Holdings Inc. ("CGMH") is the sole stockholder of CFP. Citigroup Inc. is the sole stockholder of CGMH.

Remarks:

	Citigroup Inc., By: /s/ Ali L. Karshan, Assistant Secretary	02/25/2015
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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