SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D/A

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO RULE 13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO

RULE 13d-2(a)

(Amendment No. 3)*

Mentor Graphics Corporation

(Name of Issuer)

Common Stock, without par value

(Title of Class of Securities)

587200106

(CUSIP Number)

Casablanca Capital LLC

450 Park Avenue, Suite 1403

New York, NY 10022

Attn: Douglas Taylor

(212) 759-5626

with a copy to:

David E. Rosewater

Schulte Roth & Zabel LLP

919 Third Avenue

New York, New York 10022

(212) 756-2000

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

March 9, 2011

(Date of Event which Requires

Filing of this Schedule)

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 Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box. [ ]

NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

(Continued on following pages)

(Page 1 of 13 Pages)

--------------------------

* 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 disclosures provided in a prior cover page.

The information required on 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.  587200106   SCHEDULE 13D/A Page 2 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Casablanca Special Opportunities Fund I, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 0
	8	SHARED VOTING POWER 573,683
	9	SOLE DISPOSITIVE POWER 0
	10	SHARED DISPOSITIVE POWER 573,683
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 573,683
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.5%
14	TYPE OF REPORTING PERSON OO

CUSIP No.  587200106   SCHEDULE 13D/A Page 3 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Casablanca Capital I LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS AF
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 0
	8	SHARED VOTING POWER 573,683
	9	SOLE DISPOSITIVE POWER 0
	10	SHARED DISPOSITIVE POWER 573,683
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 573,683
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.5%
14	TYPE OF REPORTING PERSON IA, OO

CUSIP No.  587200106   SCHEDULE 13D/A Page 4 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Casablanca Capital LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO, AF (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 0
	8	SHARED VOTING POWER 746,352
	9	SOLE DISPOSITIVE POWER 0
	10	SHARED DISPOSITIVE POWER 746,352
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 746,352
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.7%
14	TYPE OF REPORTING PERSON IA, OO

CUSIP No.  587200106   SCHEDULE 13D/A Page 5 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Donald G. Drapkin
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS PF, OO, AF (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION USA
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 25,410
	8	SHARED VOTING POWER 746,352
	9	SOLE DISPOSITIVE POWER 25,410
	10	SHARED DISPOSITIVE POWER 746,352
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 771,762
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.7%
14	TYPE OF REPORTING PERSON IN

CUSIP No.  587200106   SCHEDULE 13D/A Page 6 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Douglas Taylor
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO and AF (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION USA
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 0
	8	SHARED VOTING POWER 746,352
	9	SOLE DISPOSITIVE POWER 0
	10	SHARED DISPOSITIVE POWER 746,352
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 746,352
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.7%
14	TYPE OF REPORTING PERSON IN

CUSIP No587200106   SCHEDULE 13D/A Page 7 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Francisco D'Agostino
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO, AF (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Spain
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 0
	8	SHARED VOTING POWER 782,652
	9	SOLE DISPOSITIVE POWER 0
	10	SHARED DISPOSITIVE POWER 782,652
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 782,652
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.7%
14	TYPE OF REPORTING PERSON IN

CUSIP No.  587200106   SCHEDULE 13D/A Page 8 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Element Multi Strategy Fund Ltd.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Cayman Islands
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 0
	8	SHARED VOTING POWER 36,300
	9	SOLE DISPOSITIVE POWER 0
	10	SHARED DISPOSITIVE POWER 36,300
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 36,300
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.0%
14	TYPE OF REPORTING PERSON CO

CUSIP No587200106   SCHEDULE 13D/A Page 9 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Element Capital Advisors Ltd.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS AF
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION British Virgin Islands
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 0
	8	SHARED VOTING POWER 36,300
	9	SOLE DISPOSITIVE POWER 0
	10	SHARED DISPOSITIVE POWER 36,300
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 36,300
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 0.0%
14	TYPE OF REPORTING PERSON IA, CO

CUSIP No.  587200106   SCHEDULE 13D/A Page 10 of 13 Pages

1	NAME OF REPORTING PERSONS, I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Her Majesty the Queen in Right of the Province of Alberta as represented by Alberta Investment Management Corporation
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)		¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Alberta, Canada
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7	SOLE VOTING POWER 5,205,282
	8	SHARED VOTING POWER 0
	9	SOLE DISPOSITIVE POWER 5,205,282
	10	SHARED DISPOSITIVE POWER 0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 5,205,282
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) (see Item 5) 4.7%
14	TYPE OF REPORTING PERSON IA, OO

CUSIP No.  587200106   SCHEDULE 13D/A Page 11 of 13 Pages

This Amendment No. 3 to Schedule 13D amends and supplements the Schedule 13D (the “Original Schedule 13D”) filed with the Securities and Exchange Commission on February 3, 2011, Amendment No. 1 filed with the Securities and Exchange Commission on February 8, 2011 ("Amendment 1") and Amendment No. 2 filed with the Securities and Exchange Commission on February 14, 2011 (“Amendment 2”, and together with the Original Schedule 13D, Amendment 1 and this Amendment No. 3, the “Schedule 13D”), with respect to the common shares (the “Shares”), without par value per share, of Mentor Graphics Corporation. Except as set forth herein the Schedule 13D is unmodified.

Item 4. PURPOSE OF TRANSACTION.

Item 4 of the Schedule 13D is amended and supplemented to add the following information for updating as of the date hereof:

As previously disclosed, on February 11, 2011, the Reporting Persons delivered a letter to the Issuer notifying it that the Reporting Persons  intend  to  appear  at  the  2011  annual  meeting  of  the  Issuer's shareholders  to nominate and seek to elect certain persons to the Issuer’s board of directors (the “Board”).  The Reporting Persons believe that the Issuer needs new directors with the experience and capabilities to maximize value for all shareholders due to the Issuer’s questionable corporate governance and inefficient business practices and operations, which have reduced shareholder confidence in the management and the Board and eroded shareholder value.

On February 11, 2011, Icahn Partners LP, Icahn Partners Master Fund LP, Icahn  Partners Master Fund II LP, Icahn Partners Master Fund III LP, and High River Limited Partnership (the “Icahn Parties”) also delivered a letter (the “Icahn Letter”) to the Issuer notifying it that, amongst other things, the Icahn Parties intend  to  appear  at  the  2011  annual  meeting  of  the  Issuer's shareholders,  in  person or by proxy, to nominate and seek to elect certain persons (the “Icahn Nominees”) to the Issuer’s Board. Subsequently, on February 22, 2011, the Icahn Parties made an offer to acquire the Issuer for $17 per share in cash.

The Reporting Persons have reviewed the information and proposals contained in the Icahn Letter and other documents the Icahn Parties have filed with the SEC and support the position that the Board should explore a sale of the Issuer as a means of maximizing value for all shareholders and that the Issuer would benefit from having independent, new directors on the Board who will act in the best interests of all shareholders in conducting this process.  The Reporting Persons also believe that to avoid shareholder confusion that could arise from multiple nominations, and to create the most efficient process for electing nominees to the Board, it is in the best interests of all shareholders that only one group of shareholders nominate a competing slate of nominees for election to the Board.

In light of the reported qualifications of the Icahn Nominees, and the Icahn Parties’ ownership position and proposals, the Reporting Persons no longer intend to nominate candidates for the Board at the Issuer’s upcoming Annual Meeting.  The Reporting Persons currently intend to vote for the Icahn Nominees at the 2011 annual meeting of the Issuer’s shareholders, although the Reporting Persons do not have any commitment, agreement or understanding to do so.

Except as set forth herein, the Reporting Persons have no present plan or proposal that would relate to or result in any of the matters set forth in subparagraphs (a)-(j) of Item 4 of Schedule 13D.  The Reporting Persons intend to review their investment in the Issuer on a continuing basis and may engage in discussions with management, the Board of Directors, other shareholders of the Issuer and other relevant parties concerning matters with respect to the Reporting Persons’ investment in the Shares, including, without limitation, the business, operations, governance (including the election of directors), management, strategy and future plans of the Issuer.  Depending on various factors, including, without limitation, the outcome of any discussions referenced above, the Issuer's financial position and strategic direction, actions taken by the Board of Directors, price levels of the Shares, other investment opportunities available to the Reporting Persons, conditions in the securities market and general economic and industry conditions, the Reporting Persons may in the future take such actions with respect to their investment in the Issuer as they deem appropriate, including, without limitation, selling some or all of their Shares and/or engaging in short selling of or any hedging or similar transactions with respect to the Shares and/or otherwise changing their intention with respect to any and all matters referred to in Item 4 of Schedule 13D.

CUSIP No.  587200106   SCHEDULE 13D/A Page 12 of 13 Pages

SIGNATURES

After reasonable inquiry and to the best of his or its knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Date: March 10, 2011

	Casablanca Special Opportunities Fund I, LLC
By:	Casablanca Capital LLC, its Investment Manager
By:	/s/ Douglas Taylor
Name:	Douglas Taylor
Title:	Chief Executive Officer
	Casablanca Capital I LLC
By:	/s/ Douglas Taylor
Name:	Douglas Taylor
Title:	Chief Executive Officer
	Casablanca Capital LLC
By:	/s/ Douglas Taylor
Name:	Douglas Taylor
Title:	Chief Executive Officer
/s/ Donald G. Drapkin
Donald G. Drapkin
/s/ Douglas Taylor
Douglas Taylor
/s/ Francisco D’Agostino
Francisco D'Agostino

CUSIP No.  587200106   SCHEDULE 13D/A Page 13 of 13 Pages

	Element Multi Strategy Fund Ltd.
By:	/s/ Francisco D’Agostino
Name:	Francisco D’Agostino
Title:	Director
	Element Capital Advisors Ltd.
By:	/s/ Francisco D’Agostino
Name:	Francisco D’Agostino
Title:	President and Director
	Her Majesty the Queen in Right of the Province of Alberta as represented by Alberta Investment Management Corporation
By:	/s/ Brian Gibson
Name:	Brian Gibson
Title:	Senior Vice President, Public Equities