UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 4)*

CYMER, INC.

(Name of Issuer)

Common Stock, $0.001 Par Value Per Share

(Title of Class of Securities)

232572107

(CUSIP Number)

December 31, 2009

(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 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).

Page 1 of 9

CUSIP No.232572107

13G

Page 2 of 9 Pages

1	NAME OF REPORTING PERSON I.R.S. IDENTIFICATION NO. OF ABOVE PERSON S.A.C. Capital Advisors, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [ ] (b) [ X ]
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0
		6	SHARED VOTING POWER 12,160 (1) (see Item 4)
		7	SOLE DISPOSITIVE POWER 0
		8	SHARED DISPOSITIVE POWER 12,160 (1) (see Item 4)
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 12,160 (1) (see Item 4)
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ]
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) Less than 0.1% (1) (see Item 4)
12	TYPE OF REPORTING PERSON* PN

*SEE INSTRUCTION BEFORE FILLING OUT

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CUSIP No.232572107

13G

Page 3 of 9 Pages

1	NAME OF REPORTING PERSON I.R.S. IDENTIFICATION NO. OF ABOVE PERSON S.A.C. Capital Advisors, Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [ ] (b) [ X ]
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0
		6	SHARED VOTING POWER 12,160 (1) (see Item 4)
		7	SOLE DISPOSITIVE POWER 0
		8	SHARED DISPOSITIVE POWER 12,160 (1) (see Item 4)
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 12,160 (1) (see Item 4)
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ]
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) Less than 0.1% (1) (see Item 4)
12	TYPE OF REPORTING PERSON* CO

*SEE INSTRUCTION BEFORE FILLING OUT

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CUSIP No.232572107

13G

Page 4 of 9 Pages

1	NAME OF REPORTING PERSON I.R.S. IDENTIFICATION NO. OF ABOVE PERSON S.A.C. Arbitrage Fund, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [ ] (b) [ X ]
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Anguilla, British West Indies
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0
		6	SHARED VOTING POWER 0 (see Item 4)
		7	SOLE DISPOSITIVE POWER 0
		8	SHARED DISPOSITIVE POWER 0 (see Item 4)
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 (see Item 4)
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ]
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0% (see Item 4)
12	TYPE OF REPORTING PERSON* 00

*SEE INSTRUCTION BEFORE FILLING OUT

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CUSIP No.232572107

13G

Page 5 of 9 Pages

1	NAME OF REPORTING PERSON I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Steven A. Cohen
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [ ] (b) [ X ]
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION United States
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0
		6	SHARED VOTING POWER 12,160 (1) (see Item 4)
		7	SOLE DISPOSITIVE POWER 0
		8	SHARED DISPOSITIVE POWER 12,160 (1) (see Item 4)
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 12,160 (1) (see Item 4)
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ]
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) Less than 0.1% (1) (see Item 4)
12	TYPE OF REPORTING PERSON* IN

*SEE INSTRUCTION BEFORE FILLING OUT

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Item 1(a)

Name of Issuer:

Cymer, Inc.

Item 1(b)

Address of Issuer's Principal Executive Offices:

17075 Thornmint Court, San Diego, CA 92127

Items 2(a)

Name of Person Filing:

This statement is filed by: (i) S.A.C. Capital Advisors, L.P. (“SAC Capital Advisors LP”) with respect to shares of Common Stock, par value $0.001 per share (“Shares”) of the Issuer beneficially owned by S.A.C. MultiQuant Fund, LLC (“SAC MultiQuant Fund”); (ii) S.A.C. Arbitrage Fund, LLC (“SAC Arbitrage Fund”) with respect to shares beneficially owned by it; (iii) S.A.C. Capital Advisors, Inc. (“SAC Capital Advisors Inc.”) with respect to Shares beneficially owned by SAC Capital Advisors LP, SAC Arbitrage Fund and SAC MultiQuant Fund; and (iv) Steven A. Cohen with respect to Shares beneficially owned by SAC Capital Advisors LP, SAC Capital Advisors Inc., SAC MultiQuant Fund and SAC Arbitrage Fund.

Item 2(b)

Address of Principal Business Office:

The address of the principal business office of (i) SAC Capital Advisors LP, SAC Capital Advisors Inc. and Mr. Cohen is 72 Cummings Point Road, Stamford, Connecticut 06902; and (ii) SAC Arbitrage Fund is P.O. Box 174, Mitchell House, The Valley, Anguilla, British West Indies.

Item 2(c)

Citizenship:

SAC Capital Advisors LP is a Delaware limited partnership. SAC Capital Advisors Inc. is a Delaware corporation. SAC Arbitrage Fund is an Anguillan limited liability company. Mr. Cohen is a United States citizen.

Item 2(d)

Title of Class of Securities:

Common Stock, $0.001 par value per share

Item 2(e)

CUSIP Number:

232572107

Item 3

Not Applicable

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Item 4

Ownership:

The percentages used herein are calculated based upon the Shares issued and outstanding as of November 2, 2009 as reported on the Issuer's quarterly report on Form 10-Q filed with the Securities and Exchange Commission by the Issuer for the quarterly period ended September 30, 2009.

As of the close of business on December 31, 2009:

1. S.A.C. Capital Advisors, L.P.

(a) Amount beneficially owned: 12,160 (1)

(b) Percent of class: less than 0.1% (1)

(c)(i) Sole power to vote or direct the vote: -0-

(ii) Shared power to vote or direct the vote: 12,160 (1)

(iii) Sole power to dispose or direct the disposition: -0-

(iv) Shared power to dispose or direct the disposition: 12,160 (1)

2. S.A.C. Capital Advisors, Inc.

(a) Amount beneficially owned: 12,160 (1)

(b) Percent of class: less than 0.1% (1)

(c)(i) Sole power to vote or direct the vote: -0-

(ii) Shared power to vote or direct the vote: 12,160 (1)

(iii) Sole power to dispose or direct the disposition: -0-

(iv) Shared power to dispose or direct the disposition: 12,160 (1)

3. S.A.C. Arbitrage Fund, LLC

(a) Amount beneficially owned: -0-

(b) Percent of class: 0%

(c)(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 direct the disposition: -0-

(iv) Shared power to dispose or direct the disposition: -0-

4. Steven A. Cohen

(a) Amount beneficially owned: 12,160 (1)

(b) Percent of class: less than 0.1% (1)

(c)(i) Sole power to vote or direct the vote: -0-

(ii) Shared power to vote or direct the vote: 12,160 (1)

(iii) Sole power to dispose or direct the disposition: -0-

(iv) Shared power to dispose or direct the disposition: 12,160 (1)

(1) The number of Shares reported herein includes 2,050 Shares held in an external account for the benefit of SAC MultiQuant Fund, and managed by an external investment manager pursuant to an investment management agreement (the “External Manager Agreement”). SAC Capital Advisors LP, as investment manager to SAC MultiQuant Fund, may terminate the External Manager Agreement at any time and, by operation of Rule 13d-3 of the Securities Exchange Act, may be deemed to beneficially own such Shares.

Page 7 of 9

SAC Capital Advisors LP, SAC Capital Advisors Inc. and Mr. Cohen own directly no Shares. Pursuant to an investment management agreement, SAC Capital Advisors LP maintains investment and voting power with respect to the securities held by SAC MultiQuant Fund. SAC Capital Advisors Inc. is the general partner of SAC Capital Advisors LP. Mr. Cohen controls SAC Capital Advisors Inc. As of December 31, 2009, by reason of the provisions of Rule 13d-3 of the Securities Exchange Act of 1934, as amended, each of SAC Capital Advisors LP, SAC Capital Advisors Inc. and Mr. Cohen may be deemed to beneficially own 12,160 (1) Shares (constituting less than 0.1% (1) of the Shares outstanding). Each of SAC Capital Advisors LP, SAC Capital Advisors Inc. and Mr. Cohen disclaims beneficial ownership of any of the securities covered by this statement.

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 of securities, check the following. [ X ]

Item 6

Ownership of More than Five Percent on Behalf of Another Person:

Not Applicable

Item 7

Identification and Classification of the

Subsidiary Which Acquired the Security Being

Reported on By the Parent Holding Company:

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 the signatory certifies that, to the best of his knowledge and belief, the securities referred to above 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.

Page 8 of 9

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.

Dated: February 16, 2010

S.A.C. CAPITAL ADVISORS, L.P.

By: /s/ Peter Nussbaum

Name: Peter Nussbaum

Title: Authorized Person

S.A.C. CAPITAL ADVISORS, INC.

By: /s/ Peter Nussbaum

Name: Peter Nussbaum

Title: Authorized Person

S.A.C. ARBITRAGE FUND, LLC

By: /s/ Peter Nussbaum

Name: Peter Nussbaum

Title: Authorized Person

STEVEN A. COHEN

By: /s/ Peter Nussbaum

Name: Peter Nussbaum

Title: Authorized Person

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