SC 13G/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

(Rule 13d-102)

Information to be Included in Statements Filed Pursuant to Rule 13d-1(b), (c)

and (d) and Amendments Thereto Filed Pursuant to Rule 13d-2.

Under the Securities Exchange Act of 1934
(Amendment No. 5)*

Hawk Corporation

(Name of Issuer)

Class A Common Stock, par value $0.01

(Title of Class of Securities)

420089104

(CUSIP Number)

December 31, 2008

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

o Rule 13d-1(b)

x Rule 13d-1(c)

o 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 in 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. 420089104
	1.	Names of Reporting Persons. Discovery Equity Partners, L.P.
	2.	Check the Appropriate Box if a Member of a Group (See Instructions) Not Applicable
		(a)		o
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization Illinois
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power None
			6.		Shared Voting Power 49,142
			7.		Sole Dispositive Power None
			8.		Shared Dispositive Power 49,142
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 49,142
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o Not Applicable
	11.	Percent of Class Represented by Amount in Row (9) 0.5%
	12.	Type of Reporting Person (See Instructions) PN

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CUSIP No. 420089104
	1.	Names of Reporting Persons. Discovery Group I, LLC
	2.	Check the Appropriate Box if a Member of a Group (See Instructions) Not Applicable
		(a)		o
		(b)		o
	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 None
			6.		Shared Voting Power 57,866
			7.		Sole Dispositive Power None
			8.		Shared Dispositive Power 57,866
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 57,866
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o Not Applicable
	11.	Percent of Class Represented by Amount in Row (9) 0.6%
	12.	Type of Reporting Person (See Instructions) OO

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CUSIP No. 420089104
	1.	Names of Reporting Persons. Daniel J. Donoghue
	2.	Check the Appropriate Box if a Member of a Group (See Instructions) Not Applicable
		(a)		o
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization U.S.A.
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power None
			6.		Shared Voting Power 57,866
			7.		Sole Dispositive Power None
			8.		Shared Dispositive Power 57,866
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 57,866
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o Not Applicable
	11.	Percent of Class Represented by Amount in Row (9) 0.6%
	12.	Type of Reporting Person (See Instructions) IN

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CUSIP No. 420089104
	1.	Names of Reporting Persons. Michael R. Murphy
	2.	Check the Appropriate Box if a Member of a Group (See Instructions) Not Applicable
		(a)		o
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization U.S.A.
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power None
			6.		Shared Voting Power 57,866
			7.		Sole Dispositive Power None
			8.		Shared Dispositive Power 57,866
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 57,866
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o Not Applicable
	11.	Percent of Class Represented by Amount in Row (9) 0.6%
	12.	Type of Reporting Person (See Instructions) IN

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Item 1.
	(a)	Name of Issuer: Hawk Corporation
	(b)	Address of Issuer’s Principal Executive Offices 200 Public Square, Suite 1500, Cleveland, Ohio 44114
Item 2.
	(a)	Name of Person Filing: Discovery Equity Partners, L.P. (“Discovery Partners”) Discovery Group I, LLC, the general partner of Discovery Partners (“Discovery Group”) Daniel J. Donoghue, a Managing Member of Discovery Group Michael R. Murphy, a Managing Member of Discovery Group
	(b)	Address of Principal Business Office or, if none, Residence: Discovery Partners, Discovery Group, Mr. Donoghue, and Mr. Murphy are all located at: 191 North Wacker Drive, Suite 1685, Chicago, Illinois  60606
	(c)	Citizenship: Discovery Partners is an Illinois limited partnership Discovery Group is a Delaware limited liability company Mr. Donoghue and Mr. Murphy are U.S. citizens
	(d)	Title of Class of Securities: Class A Common Stock, par value $0.01
	(e)	CUSIP Number: 420089104
Item 3.	If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
	Not Applicable.
	(a)	o	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
	(b)	o	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
	(c)	o	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
	(d)	o	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C 80a-8);
	(e)	o	An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);
	(f)	o	An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);
	(g)	o	A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);
	(h)	o	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
	(i)	o	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
	(j)	o	Group, in accordance with §240.13d-1(b)(1)(ii)(J).

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Item 4.	Ownership
Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.
	(a)	Amount beneficially owned:    Discovery Partners – 49,142 Discovery Group – 57,866 Mr. Donoghue – 57,866 Mr. Murphy – 57,866
	(b)	Percent of class:    Discovery Partners – 0.5% Discovery Group – 0.6% Mr. Donoghue – 0.6% Mr. Murphy – 0.6% The foregoing percentages are based on 8,979,677 shares of Class A Common Stock of the Issuer outstanding as of November 1, 2008, as reported in the Issuer’s Quarterly Report on Form 10-Q for the period ended September 30, 2008.
	(c)	Number of shares as to which the person has:
		(i)	Sole power to vote or to direct the vote    None
		(ii)	Shared power to vote or to direct the vote     Discovery Partners – 49,142 Discovery Group – 57,866 Mr. Donoghue – 57,866 Mr. Murphy – 57,866
		(iii)	Sole power to dispose or to direct the disposition of    None
		(iv)	Shared power to dispose or to direct the disposition of    Discovery Partners – 49,142 Discovery Group – 57,866 Mr. Donoghue – 57,866 Mr. Murphy – 57,866
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 or Control Person
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 I certify that, to the best of my 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.

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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.

February 13, 2009

Date

DISCOVERY GROUP I, LLC,
for itself and as general partner of
DISCOVERY EQUITY PARTNERS, L.P.

Michael R. Murphy*

Signature

Michael R. Murphy, Managing Member

Name/Title

Daniel J. Donoghue*

Signature

Daniel J. Donoghue

Name/Title

Michael R. Murphy*

Signature

Michael R. Murphy

Name/Title

*By: /s/ Mark Buckley

Mark Buckley
Attorney-in-Fact for Daniel J. Donoghue
Attorney-in-Fact for Michael R. Murphy

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Exhibit Index

Exhibit 1	Joint Filing Agreement dated as of February 13, 2009, by and among Discovery Equity Partners; L.P.; Discovery Group I, LLC; Daniel J. Donoghue; and Michael R. Murphy
Exhibit 2	Power of Attorney of Daniel J. Donoghue, dated as of April 28, 2008
Exhibit 3	Power of Attorney of Michael R. Murphy, dated as of April 28, 2008

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EX-1

EXHIBIT 1

JOINT FILING AGREEMENT

The undersigned hereby agree to the joint filing of the Amendment No. 5 to the Schedule 13G to which this Agreement is attached.

Dated:  February 13, 2009

DISCOVERY GROUP I, LLC,
for itself and as general partner of
DISCOVERY EQUITY PARTNERS, L.P.
By	Michael R. Murphy*
	Michael R. Murphy
	Managing Member
Daniel J. Donoghue*
Daniel J. Donoghue
Michael R. Murphy*
Michael R. Murphy
*By:		/s/ Mark Buckley
		Mark Buckley
		Attorney-in-Fact for Daniel J. Donoghue
		Attorney-in-Fact for Michael R. Murphy

EX-2

EXHIBIT 2

POWER OF ATTORNEY

The undersigned, Daniel J. Donoghue, hereby appoints Mark Buckley his true and lawful attorney-in-fact and agent, with full power to execute and file with the United States Securities and Exchange Commission and any stock exchange or similar authority, for and on his behalf in any and all capacities, any and all reports required to be filed pursuant to Section 13 of the Securities Exchange Act of 1934 and the rules thereunder on Schedule 13D or 13G, any and all amendments to such reports, with all exhibits, and any other forms or documents as may be necessary in connection with the filing of such reports with the United States Securities and Exchange Commission and any stock exchange or similar authority, granting unto said attorney full power and authority to do and perform any and all acts for and on behalf of the undersigned which may be necessary or desirable to complete, as fully as the undersigned might or could do in person.

This Power of Attorney shall remain in full force and effect until revoked by the undersigned in a signed writing delivered to the foregoing attorney-in-fact and agent.

                IN WITNESS WHEREOF the undersigned has caused this Power of Attorney to be executed this 28th day of April, 2008.

/s/ Daniel J. Donoghue

Daniel J. Donoghue

STATE OF ILLINOIS	)
	) SS.
COUNTY OF COOK	)

I, Kareema M. Cruz, a Notary Public in and for the County of Cook, State of Illinois, DO HEREBY CERTIFY that Daniel J. Donoghue, who is personally known to me to be the same person whose name is subscribed to the foregoing instrument, appeared before me this day in person and acknowledged that he signed and delivered the said instrument as his own free and voluntary act, for the uses and purposes therein set forth.

Given under my hand and notarial seal, this 28th day of April, 2008.

/s/ Kareema M. Cruz

Notary Public

EX-3

EXHIBIT 3

POWER OF ATTORNEY

The undersigned, Michael R. Murphy, hereby appoints Mark Buckley his true and lawful attorney-in-fact and agent, with full power to execute and file with the United States Securities and Exchange Commission and any stock exchange or similar authority, for and on his behalf in any and all capacities, any and all reports required to be filed pursuant to Section 13 of the Securities Exchange Act of 1934 and the rules thereunder on Schedule 13D or 13G, any and all amendments to such reports, with all exhibits, and any other forms or documents as may be necessary in connection with the filing of such reports with the United States Securities and Exchange Commission and any stock exchange or similar authority, granting unto said attorney full power and authority to do and perform any and all acts for and on behalf of the undersigned which may be necessary or desirable to complete, as fully as the undersigned might or could do in person.

This Power of Attorney shall remain in full force and effect until revoked by the undersigned in a signed writing delivered to the foregoing attorney-in-fact and agent.

IN WITNESS WHEREOF the undersigned has caused this Power of Attorney to be executed this 28th day of April, 2008.

/s/ Michael R. Murphy

Michael R. Murphy

STATE OF ILLINOIS	)
	)SS.
COUNTY OF COOK	)

I, Kareema M. Cruz, a Notary Public in and for the County of Cook, State of Illinois, DO HEREBY CERTIFY that Michael R. Murphy, who is personally known to me to be the same person whose name is subscribed to the foregoing instrument, appeared before me this day in person and acknowledged that he signed and delivered the said instrument as his own free and voluntary act, for the uses and purposes therein set forth.

Given under my hand and notarial seal, this 28th day of April, 2008.

/s/ Kareema M. Cruz

Notary Public