SC 13D/A

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934
(Amendment No. 4)*

STRATEGIC DIAGNOSTICS INC.

(Name of Issuer)

Common Stock, par value $0.01 per share

(Title of Class of Securities)

862700101

(CUSIP Number)

Becker Drapkin Management, L.P.
Attn: Steven R. Becker
300 Crescent Court, Suite 1111
Dallas, Texas 75201
(214) 756-6156

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

August 29, 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. þ

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.

* 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. 862700101 

1	NAMES OF REPORTING PERSONS Becker Drapkin Management, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
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)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			0
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			2,474,604
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			0
WITH		10	SHARED DISPOSITIVE POWER
			2,474,604
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	2,474,604
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	12.0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IA, PN

CUSIP No. 862700101 

1	NAMES OF REPORTING PERSONS Becker Drapkin Partners (QP), L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			2,211,800
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			2,211,800
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	2,211,800
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	10.7%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	PN

CUSIP No. 862700101 

1	NAMES OF REPORTING PERSONS Becker Drapkin Partners, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			262,804
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			262,804
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	262,804
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	1.3%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	PN

CUSIP No. 862700101 

1	NAMES OF REPORTING PERSONS BC Advisors, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
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)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			0
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			2,474,604
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			0
WITH		10	SHARED DISPOSITIVE POWER
			2,474,604
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	2,474,604
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	12.0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

CUSIP No. 862700101 

1	NAMES OF REPORTING PERSONS Steven R. Becker
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	AF, PF
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States
		7	SOLE VOTING POWER
NUMBER OF			185,9101
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			2,474,604
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			185,9101
WITH		10	SHARED DISPOSITIVE POWER
			2,474,604
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	2,660,5141
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	12.9%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

¹Includes 23,021 shares of common stock of the issuer that the reporting person has the right to acquire within 60 days of the date of this Schedule 13D pursuant to stock options to purchase shares of common stock of the issuer.

CUSIP No. 862700101 

1	NAMES OF REPORTING PERSONS Matthew A. Drapkin
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
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)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States
		7	SOLE VOTING POWER
NUMBER OF			0
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			2,474,604
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			0
WITH		10	SHARED DISPOSITIVE POWER
			2,474,604
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	2,474,604
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	12.0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

This Amendment No. 4 to Schedule 13D (this “Amendment”) is filed by and on behalf of each of the Reporting Persons to amend the Schedule 13D related to the common stock of the issuer (the “Common Stock”) filed with the Securities and Exchange Commission (the “Commission”) on February 15, 2008, as amended and/or supplemented by Amendment No. 1 to the Schedule 13D filed on March 4, 2008, Amendment No. 2 to the Schedule 13D filed on March 18, 2008 and Amendment No. 3 to the Schedule 13D filed on August, 10, 2010 by the Reporting Persons with the Commission (as amended, the “Schedule 13D”). This Amendment is filed to disclose a change in the beneficial ownership of each Reporting Person relating to the acquisition of shares of Common Stock. Each capitalized term used and not defined herein shall have the meaning assigned to such term in the Schedule 13D. Except as otherwise provided herein, each Item of the Schedule 13D remains unchanged.

Item 2. Identity and Background.

Item 2 of the Schedule 13D is hereby amended and supplemented to add the following information for updating the Schedule 13D as of the date hereof:

On August 18, 2010, SRB Management changed its name to Becker Drapkin Management, L.P. (“BD Management”), QP Fund changed its name to Becker Drapkin Partners (QP), L.P. (“Becker Drapkin QP”), and LP Fund changed its name to Becker Drapkin Partners, L.P. (“Becker Drapkin LP”). Becker Drapkin QP and Becker Drapkin LP are referred to collectively as the “Becker Drapkin Funds.” SRB Management, QP Fund and LP Fund are hereinafter referred to as BD Management, Becker Drapkin QP and Becker Drapkin LP, respectively.

Item 3. Source and Amount of Funds or Other Consideration.

Item 3 of the Schedule 13D is hereby amended and restated in its entirety as follows:

Becker Drapkin QP and Becker Drapkin LP have acquired an aggregate of 2,474,604 shares of Common Stock, which are reported herein, in multiple open market transactions for an aggregate purchase price of $5,946,220.34 (excluding commissions). The source of funds for the purchase of Common Stock was the general working capital of Becker Drapkin QP and Becker Drapkin LP.

Becker has acquired an aggregate of 162,889 shares of Common Stock and may be deemed, under Rule 13d-3 of the Exchange Act, to beneficially own 23,021 shares of Common Stock that may be acquired within 60 days of the date of this Amendment pursuant to stock options. The shares of Common Stock and options were acquired in multiple awards from the issuer and in multiple open market transactions for an aggregate purchase price of $232,586.27 (excluding commissions). The source of funds for the purchase of Common Stock was Becker’s personal funds.

Item 5. Interest in Securities of the Issuer.

Item 5(a) is amended and restated in its entirety as follows:

(a) Each Reporting Person declares that neither the filing of this statement nor anything herein shall be construed as an admission that such person is, for the purposes of Section 13(d) or 13(g) of the Act or any other purpose, the beneficial owner of any securities covered by this statement.

The aggregate number and percentage of the class of securities identified pursuant to Item 1 beneficially owned by each Reporting Person is stated in Items 11 and 13 on the cover page(s) hereto.

Item 5(b) is amended and restated in its entirety as follows:

(b) Number of shares as to which each Reporting Person has:

(i)	sole power to vote or to direct the vote:
	See Item 7 on the cover page(s) hereto.

(ii)	shared power to vote or to direct the vote:
	See Item 8 on the cover page(s) hereto.
(iii)	sole power to dispose or to direct the disposition of:
	See Item 9 on the cover page(s) hereto.
(iv)	shared power to dispose or to direct the disposition of:
	See Item 10 on the cover page(s) hereto.

Becker has the power to vote or to direct the vote of (and the power to dispose or direct the disposition of) the shares of Common Stock owned by him (the “Becker Shares”). Becker disclaims beneficial ownership of the Becker Drapkin QP Shares and the Becker Drapkin LP Shares (each, as defined below).

Becker Drapkin QP has the power to vote or to direct the vote of (and the power to dispose or direct the disposition of) the shares owned by it (the “Becker Drapkin QP Shares”). Becker Drapkin QP disclaims beneficial ownership of the Becker Shares and the Becker Drapkin LP Shares.

Becker Drapkin LP has the power to vote or to direct the vote of (and the power to dispose or direct the disposition of) the shares owned by it (the “Becker Drapkin LP Shares,” and together with the Becker Drapkin QP Shares, the “Becker Drapkin Funds Shares”). Becker Drapkin LP disclaims beneficial ownership of the Becker Shares and the Becker Drapkin QP Shares.

As general partner of each of the Becker Drapkin Funds, BD Management may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) the Becker Drapkin Funds Shares. BD Management does not own any shares of Common Stock directly and disclaims beneficial ownership of the Becker Drapkin Funds Shares.

As general partner of BD Management, BCA may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) any shares of Common Stock beneficially owned by BD Management. BCA does not own any shares of Common Stock directly and disclaims beneficial ownership of any shares of Common Stock beneficially owned by BD Management.

As co-managing members of BCA, each of Becker and Drapkin may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) any shares of Common Stock beneficially owned by BCA. Each of Becker and Drapkin disclaims beneficial ownership of any shares of Common Stock beneficially owned by BCA.

As of the date hereof, no Reporting Person owns any Common Stock other than as set forth in this Item 5.

Item 5(c) is amended and restated in its entirety as follows:

(c) Transactions in the class of securities reported on that were effected during the past sixty days or since the most recent filing of Schedule 13D, whichever is less, by the Reporting Persons are described below:

Transaction	Effecting	Shares		Shares	Price			Description
Date	Person(s)	Acquired		Disposed	Per Share			of Transaction
08/29/2011	Becker Drapkin QP		129,231		$	1.85	(1)	Open Market
08/29/2011	Becker Drapkin QP		21,800		$	1.85	(2)	Open Market
08/29/2011	Becker Drapkin LP		18,969		$	1.85	(1)	Open Market
08/29/2011	Becker Drapkin LP		3,200		$	1.85	(2)	Open Market
08/30/2011	Becker Drapkin QP		4,099		$	1.81	(2)	Open Market
08/30/2011	Becker Drapkin LP		601		$	1.81	(2)	Open Market

(1)	Excluding commission of $0.01 per share.
(2)	Excluding commission of $0.015 per share.

Item 7. Material to be Filed as Exhibits.

The following exhibits are filed as exhibits hereto:

Exhibit		Description of Exhibit
	24.1	Power of Attorney (furnished herewith)
	99.1	Joint Filing Agreement (furnished herewith)

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.

Date: August 31, 2011	BECKER DRAPKIN MANAGEMENT, L.P.
	By:	BC Advisors, LLC, its general partner
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	BECKER DRAPKIN PARTNERS (QP), L.P.
	By:	Becker Drapkin Management, L.P., its general partner
	By:	BC Advisors, LLC, its general partner
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	BECKER DRAPKIN PARTNERS, L.P.
	By:	Becker Drapkin Management, L.P., its general partner
	By:	BC Advisors, LLC, its general partner
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	BC ADVISORS, LLC
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	STEVEN R. BECKER
	/s/ Ashley Sekimoto
	Name:	Ashley Sekimoto
	Title:	Attorney-in-Fact
	MATTHEW A. DRAPKIN
	/s/ Ashley Sekimoto
	Name:	Ashley Sekimoto
	Title:	Attorney-in-Fact

EXHIBIT INDEX

Exhibit		Description of Exhibit
	24.1	Power of Attorney (furnished herewith)
	99.1	Joint Filing Agreement (furnished herewith)

EX-24.1

EXHIBIT 24.1

POWER OF ATTORNEY

August 31, 2011

Know all men by these presents, that each of Becker Drapkin Management, L.P., Becker Drapkin Partners (QP), L.P., Becker Drapkin Partners, L.P., BC Advisors, LLC, Steven R. Becker and Matthew A. Drapkin hereby constitutes and appoints Ashley Sekimoto, as the true and lawful attorney-in-fact and agent of such party with full power and authority and full power of substitution and resubstitution, for, in the name of, and on behalf of such party, place and stead, in any and all capacities, (i) to execute any and all filings required by such party under Section 13 or Section 16 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (or any similar rule with respect to foreign exchanges) or any rule or regulation thereunder (including any amendment, supplement, and/or exhibit thereto), for, in the name of, and on behalf of such party, (ii) to do and perform any and all acts for, in the name of, and on behalf of such party which said attorney-in-fact determines may be necessary or appropriate to complete and execute any and all such filings, amendments, supplements and/or exhibits and any and all other document(s) in connection therewith, (iii) to file such filings, amendments, supplements, exhibits and/or documents with any governmental office or agency, whether U.S., foreign, state or local government (including, without limitation, the U.S. Securities and Exchange Commission and state securities administrators or commissions), or any stock exchange or stock quotation system, as may be required under applicable laws or rules and regulations of any stock exchange or stock quotation system, and (iv) to perform any and all other acts that said attorney-in-fact or agent determines may be necessary or appropriate in connection with the foregoing that may be in the best interest of or legally required by such party, granting unto said attorney-in-fact and agent full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises, as fully to all intents and purposes as such party might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent shall do or cause to be done by virtue hereof. Each of Becker Drapkin Management, L.P., Becker Drapkin Partners (QP), L.P., Becker Drapkin Partners, L.P., BC Advisors, LLC, Steven R. Becker and Matthew A. Drapkin hereby acknowledges that the foregoing attorney-in-fact and agent in serving in such capacity at the request of such party, is not assuming any of the responsibilities of such party to comply with Section 16 or Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder.

Remainder of Page Intentionally Left Blank. Signature Page(s) to Follow.

IN WITNESS WHEREOF, each party hereto has caused this agreement to be executed and effective as of the date first written above.

Date: August 31, 2011	BECKER DRAPKIN MANAGEMENT, L.P.
	By:	BC Advisors, LLC, its general partner
	By:	/s/ Steven R. Becker
		Name:	Steven R. Becker
		Title:	Managing Member
	BECKER DRAPKIN PARTNERS (QP), L.P.
	By:	Becker Drapkin Management, L.P., its general partner
	By:	BC Advisors, LLC, its general partner

By:	/s/ Steven R. Becker
	Name:	Steven R. Becker
	Title:	Managing Member

BECKER DRAPKIN PARTNERS, L.P.
By:	Becker Drapkin Management, L.P., its general partner
By:	BC Advisors, LLC, its general partner

By:	/s/ Steven R. Becker
	Name:	Steven R. Becker
	Title:	Managing Member

BC ADVISORS, LLC
By:	/s/ Steven R. Becker
	Name:	Steven R. Becker
	Title:	Managing Member

STEVEN R. BECKER
 

/s/ Steven R. Becker  

MATTHEW A. DRAPKIN
 

/s/ Matthew A. Drapkin  

EX-99.1

EXHIBIT 99.1

JOINT FILING AGREEMENT

August 31, 2011

Pursuant to and in accordance with the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and the rules and regulations thereunder, each party hereto hereby agrees to the joint filing, on behalf of each of them, of any filing required by such party under Section 13 or Section 16 of the Exchange Act or any rule or regulation thereunder (including any amendment, restatement, supplement and/or exhibit thereto) with the Securities and Exchange Commission (and, if such security is registered on a national securities exchange, also with the exchange), and further agrees to the filing, furnishing and/or incorporation by reference of this agreement as an exhibit thereto. This agreement shall remain in full force and effect until revoked by any party hereto in a signed writing provided to each other party hereto, and then only with respect to such revoking party.

Remainder of Page Intentionally Left Blank. Signature Page(s) to Follow.

IN WITNESS WHEREOF, each party hereto, being duly authorized, has caused this agreement to be executed and effective as of the date first written above.

Date: August 31, 2011	BECKER DRAPKIN MANAGEMENT, L.P.
	By:	BC Advisors, LLC, its general partner
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	BECKER DRAPKIN PARTNERS (QP), L.P.
	By:	Becker Drapkin Management, L.P., its general partner
	By:	BC Advisors, LLC, its general partner
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	BECKER DRAPKIN PARTNERS, L.P.
	By:	Becker Drapkin Management, L.P., its general partner
	By:	BC Advisors, LLC, its general partner
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	BC ADVISORS, LLC
	By:	/s/ Ashley Sekimoto
		Name:	Ashley Sekimoto
		Title:	Attorney-in-Fact
	STEVEN R. BECKER
	/s/ Ashley Sekimoto
	Name:	Ashley Sekimoto
	Title:	Attorney-in-Fact
	MATTHEW A. DRAPKIN
	/s/ Ashley Sekimoto
	Name:	Ashley Sekimoto
	Title:	Attorney-in-Fact