Blackrock Municipal Income Investment Trust (BBF) N-PX Annual report of proxy voting record

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-PX

ANNUAL REPORT OF PROXY VOTING RECORD OF REGISTERED MANAGEMENT

INVESTMENT COMPANY

Investment Company Act file number: 811-10333

Name of Fund: BlackRock Municipal Income Investment Trust (BBF)

Fund Address: 100 Bellevue Parkway, Wilmington, DE 19809

Name and address of agent for service: John Perlowski, Chief Executive Officer, BlackRock Municipal Income Investment Trust, 55 East 52^nd Street, New York City, NY 10055.

Registrant’s telephone number, including area code: (800) 882-0052, Option 4

Date of fiscal year end: 07/31

Date of reporting period: 07/01/2016 – 06/30/2017

Item 1 – Proxy Voting Record – Attached hereto.

******************************* FORM N-Px REPORT *******************************

ICA File Number: 811-10333
Reporting Period: 07/01/2016 - 06/30/2017
BlackRock Municipal Income Investment Trust









================= BlackRock Municipal Income Investment Trust ==================


CHILDREN'S TRUST, PUERTO RICO

Ticker:                      Security ID:  16876QBF5
Meeting Date: MAR 30, 2017   Meeting Type: Written Consent
Record Date:  NOV 17, 2016

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     By Marking For I Direct The             None      Against      Management
      Institution Holding My Bonds to
      Transmit and Confirm My Bond Holding
      Information for Recording In The
      Registry. By Marking Against My Bonds
      Shall Be Missing From The Registry.


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CHILDREN'S TRUST, PUERTO RICO

Ticker:                      Security ID:  16876QBG3
Meeting Date: MAR 30, 2017   Meeting Type: Written Consent
Record Date:  NOV 17, 2016

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     By Marking For I Direct The             None      Against      Management
      Institution Holding My Bonds to
      Transmit and Confirm My Bond Holding
      Information for Recording In The
      Registry. By Marking Against My Bonds
      Shall Be Missing From The Registry.

========== END NPX REPORT

Pursuant to the requirements of the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

BlackRock Municipal Income Investment Trust

By:	/s/ John Perlowski
	John Perlowski
	Chief Executive Officer of
	BlackRock Municipal Income Investment Trust
Date:	August 25, 2017