Blackrock Investment Quality Municipal Income Trust (RFA) SC 13D/A BLACKROCK INVESTMENT QUALITY MUNICIPAL INCOME TRUST / Karpus Management ownership change

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549SCHEDULE 13D/A
(Amendment No. 4)
Under the Securities Exchange Act of 1934BlackRock Investment Quality Municipal Income Trust (RFA)
(Name of Issuer)Auction Rate Municipal Preferred Shares
(Title of Class of Securities)09247B208
(CUSIP Number)George W. Karpus, President
Karpus Management, Inc.,
d/b/a Karpus Investment Management
183 Sully's Trail
Pittsford, New York 14534
(585) 586-4680
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)April 18, 2011
(Date of Event which Requires Filing of this Statement)If the filing person has previously filed a statement on Schedule 13G
to report the acquisition that is the subject of this Schedule 13D,
and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or
240.13d-1(g), check the following box. CUSIP No.: 09247B2081. Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only).Karpus Management, Inc., d/b/a Karpus Investment Management
I.D. #16-1290558
2. Check the Appropriate Box if a Member of a Group (See Instructions)
(a) 
(b) X
3. SEC Use Only
4. Source of Funds (See Instructions)AF
5. Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)N/A
6. Citizenship or Place of OrganizationNew York
Number of Shares Beneficially Owned by Each reporting Person With:

7. Sole Voting Power718. Shared Voting PowerN/A9. Sole Dispositive Power7110. Shared Dispositive PowerN/A

11. Aggregate Amount Beneficially Owned by Each Reporting Person71
12. Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)N/A
13. Percent of Class Represented by Amount in Row (11)38.8%*
14. Type of Reporting Person (See Instructions)IA
*Item 13, above, is calculated based on the aggregate amount of 183 outstanding auction rate preferred shares indicated by the Issuer's N-CSR filing, filed with the U.S. Securities and Exchange Commission on November 08, 2010, dated as of August 31, 2010.

The following constitutes Amendment No. 4 ("Amendment No. 4") to the Schedule 13D filed by the undersigned. This Amendment amends the original Schedule 13D as specifically set forth.

Item 3. Source and Amount of Funds or Other Considerations.KIM, an independent investment advisor, has accumulated 71 shares of RFA Auction Rate Municipal Preferred Shares on behalf of accounts that are managed by KIM (the “Accounts”) under limited powers of attorney, which represents 38.8% of the outstanding shares. All funds that have been utilized in making such purchases are from such Accounts.Item 4. Purpose of Transaction.KIM has purchased Shares for the Accounts for investment purposes. However, KIM reserves the right to contact management with regard to concerns that they have with respect to the Fund. This may include letters to the Board and/or other communications with Fund management. Being an independent registered investment advisor, with a specialty focus in closed end funds, the profile of the RFA Auction Rate Municipal Preferred Shares fits the investment guidelines for various Accounts. Shares have been acquired since April 19, 2010.Item 5. Interest in Securities of the Issuer.(a) As of the date of this Report, KIM represents beneficial ownership of 71 shares or 38.8% of the outstanding shares. None of the principals of KIM presently own shares of RFA Auction Rate Municipal Preferred Shares.(b) KIM has the sole power to dispose of and to vote all of such Shares under limited powers of attorney.(c) Open market purchases for the last 60 days for the Accounts. There have been no dispositions and no acquisitions, other than by such open market purchases:

	Date	Shares	Price Per Share
	4/18/2011	(5)	$21,500

The Accounts have the right to receive all dividends from, and any proceeds from the sale of the Shares. None of the Accounts has an interest in Shares constituting more than 5% of the Shares outstanding.Item 6. Contracts, Arrangements, Understandings, or Relationships with Respect to Securities of the Issuer.Except as described above, there are no contracts, arrangements, understandings or relationships of any kind among the Principals and KIM and between any of them and any other person with respect to any of the RFA Auction Rate Municipal Preferred Shares.Item 7. Materials to be Filed as Exhibits.As is indicated in Item 4, above, KIM has purchased RFA Auction Rate Municipal Preferred Shares for the Accounts for investment purposes. However, KIM has reserved the right to contact management with regard to concerns that they have with respect to the Fund, including letters to the Board and/or other communications with fund management. Accordingly, KIM sent a proposal letter to the fund on February 23, 2011. KIM also sent a revised proposal to the Fund on March 25, 2011. A copy of the revised proposal and the transmittal cover letter are attached as Exhibit 1.SIGNATUREAfter 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.

Karpus Management, Inc.


By:  	/s/
Name:  	Cody B. Bartlett Jr., CFA
Title:  	Managing Director of Investments
Date:  	April 28, 2011