SC 13D/A

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. 1)*

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)

February 7, 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. [ ]

(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 25,310
	8	SHARED VOTING POWER 746,352
	9	SOLE DISPOSITIVE POWER 25,310
	10	SHARED DISPOSITIVE POWER 746,352
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH PERSON 771,662
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. 1 to Schedule 13D amends and supplements the Schedule 13D (the “Original Schedule 13D” and together with this Amendment, the “Schedule 13D”) filed with the Securities and Exchange Commission on February 3, 2011, 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.

On February 4, 2011, the Issuer announced in a Current Report filed with the Securities and Exchange Commission on Form 8-K that on January 17, 2011, the Issuer’s board of directors set the date for its 2011 annual meeting of shareholders on May 12, 2011.  According to the Issuer’s bylaws, when an annual meeting of shareholders is scheduled beyond 30 days prior to the anniversary of the Issuer’s previous annual meeting (which was held on July 1, 2010), the deadline for shareholders to nominate candidates for election to the Issuer’s board of directors is accelerated from the original deadline of April 2, 2011 to a date that is 90 days prior to the new date of the Annual Meeting or 10 days after the announcement of the meeting date, if later.  Based on the May 12, 2011 rescheduled date of the 2011 annual meeting of shareholders, should any shareholder of the Issuer wish to nominate a slate of directors to the board at the 2011 annual meeting of shareholders they would need to nominate such candidates no later than 10 days after the announcement of the meeting date, such date being February 14, 2011.  Had the Issuer reported its board of directors’ setting of the date of the 2011 annual meeting of shareholders within 4 days of the January 17, 2011 determination thereof, a shareholder would have had 21 days from such disclosure to determine whether or not to nominate persons for election at the annual meeting and to organize the nominees and information in order to meet the advance notification deadline in the Bylaws.

The Reporting Persons believe that the Issuer’s operations may be improved, and hope to engage in an open and constructive dialogue with the board of directors and management of the Issuer regarding its assets, business, strategy, financial condition and operations.  On February 7, 2011, Casablanca sent the board of directors a letter, a copy of which is attached as Exhibit 4 hereto (the “Casablanca Meeting Date Letter”), in response to the actions regarding and consequences of the meeting date described above wherein Casablanca (i) expresses its concerns and disappointment about the curtailment of shareholder rights resulting from their actions with respect to the meeting date, (ii) asks to be afforded the opportunity to engage in an open and constructive dialogue with the board to express concerns as shareholders, and to give the board a meaningful opportunity to be responsive to such concerns, (iii) strongly urges the board to change the date of the annual meeting to such a time that is not more than thirty days prior to the first anniversary of the preceding year’s annual meeting and to restore the advance notification deadline for nominations to its original date of April 2, 2011 as stated in the Issuer’s 2010 proxy statement and (iv) notifies the board of Casablanca's intention to nominate an alternative slate of directors.  The description of the Casablanca Meeting Date Letter in this Schedule 13D is qualified in its entirety by reference to the full text of the Casablanca Meeting Date Letter, which is incorporated by reference herein.

Item 7. MATERIAL TO BE FILED AS EXHIBITS.

Exhibit	Description
4	Letter dated February 7, 2011 from Casablanca Capital LLC to board of directors of Mentor Graphics Corporation.

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: February 7, 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

EX-99

EXHIBIT 4

Casablanca Capital LLC

450 Park Avenue, Suite 1403

New York, New York 10022

February 7, 2011

BY EMAIL & FEDEX

Mentor Graphics Corporation

8005 S.W. Boeckman Road

Wilsonville, OR

Attn: Board of Directors

Dear Board of Directors:

Casablanca Capital LLC is a research driven investment manager.  Casablanca Capital, and, on behalf of its affiliated funds, managed accounts, certain investment advisory clients and funds under common control (“Casablanca” or “we”) and Donald Drapkin, Chairman of Casablanca (“Drapkin”, and together with Casablanca, the “Investors”), collectively have beneficial ownership in Mentor Graphics Corporation (“Mentor” or the “Company”) of more than 6 million shares, or approximately 5.5%, of the Company’s outstanding common stock.

The Investors acquired their shares because we considered, and continue to consider, Mentor’s stock to be undervalued.  As you know, the Investors believe that Mentor’s operations could be meaningfully improved to increase shareholder value, and we had hoped (and continue to hope) to engage in an open and constructive dialogue with you and Company management regarding Mentor’s assets, business, strategy, financial condition and operations.

We were hopeful that you would be responsive to our concerns and suggestions, as well as to those of other shareholders.  However, we were very disappointed that you have made unprecedented changes to the timing of your annual meeting and, as a consequence, have impacted the early notification requirements for shareholders who intend to nominate directors to your Board.  You have made such changes even though you have known for some time of the issues that other shareholders have raised, and in spite of the fact that we had just filed a required Schedule 13D with the Securities and Exchange Commission detailing our share ownership and intention to engage you in constructive discussions.  In the best interests of all shareholders, we are requesting that you promptly reverse this unfortunate and ill-conceived act of entrenchment and engage in meaningful discussions with us now.

As disclosed in your public filings, on January 17, 2011 the Board determined that it would hold the Company’s 2011 Annual Meeting on May 12, 2011.  It is disturbing that you failed to disclose that determination to shareholders for almost 3 weeks, finally announcing the date in a Current Report filed with the SEC on Form 8-K on February 4, 2011.  This is a very meaningful decision to have made as according to the Company’s bylaws, when the annual meeting is accelerated beyond 30 days prior to the anniversary of the Company’s last Annual

Mentor Graphics Corporation

February 7, 2011

Page 2

Meeting, the deadline for shareholders to nominate candidates for election to the Board of Directors (the “Advance Notice Deadline”) is accelerated from the original deadline of April 2, 2011 to a date that is 90 days prior to the new date of the Annual Meeting or 10 days after the announcement of the meeting date, if later.  You then compounded this deadline acceleration gamesmanship by delaying the announcement by 18 days, which, according to the Company’s bylaws, would ensure the minimum possible amount of time for a shareholder to determine whether or not to nominate persons for election at the Annual Meeting and to organize the nominees and information in order to me et the advance notification deadline in the Bylaws.  Failure to meet the accelerated deadline would prohibit a shareholder from nominating board candidates until at least the 2012 Annual Meeting.

If the Company had made a timely announcement of the Annual Meeting Date (for example, within two days of the determination), any shareholder would have had 23 days from such disclosure prior to the Advance Notice Deadline.  However, because information was not disclosed until 18 days after such decision was taken by the Company, that period was cut by more than half with little warning, to the minimum of 10 days.

This action is also inconsistent with the representations made in the Company’s 2010 Proxy Statement, where it was stated that “For any shareholder proposal or nomination to be considered at the 2011 Annual Meeting of Shareholders, the shareholder’s notice must be received at the Company’s principal executive office no later than April 2, 2011.”  That statement has never been updated in spite of the changes caused by the provisions of the Bylaws that would suggest that it is no longer accurate and is misleading to investors and shareholders who have, and continue to, rely on that statement.

We desire a cooperative relationship, one in which we use our collective decades of operational experience to assist the Company in maximizing its financial position for the benefit of all shareholders, employees and customers of Mentor.  Your actions threaten to make that impossible.  There is little chance for constructive, detailed dialogue with shareholders in the short 10-day period that was implemented without warning.  Never in the time that Mentor has filed its proxy statements electronically with the SEC has the Board EVER set the annual meeting more than eight days p rior to the first anniversary of the preceding year’s annual meeting, as it did here, and not since 2006 has the Board set the date of the annual meeting prior to such anniversary date for any amount of time.  The Investors are concerned that you may have deviated from traditional timing because you recognize that certain shareholders, not limited to us, have demonstrated an interest in engaging management to discuss the affairs of Mentor.  These entrenching actions require shareholders to evaluate the incumbent Board’s dedication to shareholders and consider whether you are putting your personal positions with Mentor ahead of the interests of all shareholders.

We had intended to engage in meaningful discussions with the Company before determining whether to run an alternative slate of nominees for the annual meeting.  Your highly questionable actions, however, have virtually eliminated time for any such discussions and have left us with no choice but to nominate an alternative slate of directors for the annual meeting who we know would willingly engage in open and constructive dialogue with shareholders. We are hopeful that, recognizing our current concerns, you will engage in remedial action.

Mentor Graphics Corporation

February 7, 2011

Page 3

We strongly urge you to change the date of the annual meeting to such a time that is not more than thirty days prior to the first anniversary of the preceding year’s annual meeting and to restore the advance notification deadline for nominations to its original date of April 2, 2011.

We are available, as always, to discuss issues relevant to Mentor.

Very truly yours,
CASABLANCA CAPITAL LLC
By:	/s/ Douglas Taylor
	Name:  Douglas Taylor
	Title:  Chief Executive Office

cc:    David E. Rosewater

Schulte Roth & Zabel LLP

Daniel H. Skerritt

Tonkon Torp LLP