Managed Duration Investment Grade Municipal Fund (MZF) SC 13G/A Managed Duration Investment Grade Municipal Fund

UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C.  20549__________

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

Managed Duration Investment Grade Municipal Fund

(Name of Issuer)

Common Shares

(Title of Class of Securities)

56165R103

(CUSIP Number)

December 31, 2018

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☒Rule 13d-1(b)

☐Rule 13d-1(c)

☐Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 56165R103 (See Item 2(e)) 13G Page   2  of   5  Pages

1.	NAME OF REPORTING PERSON  RIVERNORTH CAPITAL MANAGEMENT, LLC
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)  ☐ (b)  ☐
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATIONDELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:		5.	SOLE VOTING POWER0
		6.	SHARED VOTING POWER0
		7.	SOLE DISPOSITIVE POWER0
		8.	SHARED DISPOSITIVE POWER0
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON0
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES                                                                                                              ☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)0%
12.	TYPE OF REPORTING PERSONIA

CUSIP No. 56165R103 (See Item 2(e)) 13G Page   3  of   5  Pages

Item 1(a).	Name of Issuer:
	Managed Duration Investment Grade Municipal Fund
Item 1(b).	Address of Issuer’s Principal Executive Offices:
	227 West Monroe StreetChicago, IL 60606
Item 2(a).	Name of Person Filing:
	RiverNorth Capital Management, LLC
Item 2(b).	Address of Principal Business Office or, if none, Residence:
	325 N. LaSalle StreetSuite 645Chicago, IL 60654-7030
Item 2(c).	Citizenship:
	Delaware Limited Liability Company
Item 2(d).	Title of Class of Securities:
	Common Shares
Item 2(e).	CUSIP Number:
	56165R103
Item 3.	If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
	(a)	☐	Broker or dealer registered under Section 15 of the Act (15 U.S.C. 78o);
	(b)	☐	Bank as defined in Section 3(a)(6) of the Act (15 U.S.C. 78c);
	(c)	☐	Insurance company as defined in Section 3(a)(19) of the Act (15 U.S.C. 78c);
	(d)	☐	Investment company registered under Section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
	(e)	☒	An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);
	(f)	☐	An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);
	(g)	☐	A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);
	(h)	☐	A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
	(i)	☐	A church plan that is excluded from the definition of an investment company under  section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

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	(j)	☐	A non-U.S. institution in accordance with §240.13d-1(b)(1)(ii)(J);
	(k)	☐	Group, in accordance with §240.13d-1(b)(1)(ii)(K).
	If filing as a non-U.S. institution in accordance with §240.13d-1(b)(1)(ii)(J), please specify the type of institution:
Item 4.	Ownership.
	Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.
	(a)	Amount beneficially owned:  0
	(b)	Percent of class:  0%
	(c)	Number of shares as to which such person has:
		(i)Sole power to vote or direct the vote:  0
		(ii)Shared power to vote or direct the vote:  0
		(iii)Sole power to dispose or to direct the disposition of:  0
		(iv)Shared power to dispose or to direct the disposition of:  0
Item 5.	Ownership of Five Percent or Less of a Class.
	If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class securities, check the following  [X]
Item 6.	Ownership of More than Five Percent on Behalf of Another Person.
	Other persons have the right to receive the proceeds from the sale of the securities reported herein.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not applicable.
Item 8.	Identification and Classification of Members of the Group.
	Not applicable.
Item 9.	Notice of Dissolution of Group.
	Not applicable.
Item 10.	Certification.
	By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

CUSIP No. 56165R103 (See Item 2(e)) 13G Page   5  of   5  Pages

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

February 14, 2019

Date

 /s/Marcus Collins

Signature

Marcus Collins, General Counsel and

Chief Compliance Officer

Name and Title