NHWK Nighthawk Radiology Holdings, Inc. (MM)

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CUSIP No. 65411N105

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1. NAME OF REPORTING PERSON
 Water Island Capital, LLC
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2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 Not Applicable
 (a) [ ]
 (b) [ ]
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3. SEC USE ONLY
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4. CITIZENSHIP OR PLACE OF ORGANIZATION
 Delaware
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NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:
 5. SOLE VOTING POWER
 2619660
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 6. SHARED VOTING POWER
 None
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 7. SOLE DISPOSITIVE POWER
 2619660
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 8. SHARED DISPOSITIVE POWER
 None
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 2619660
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
 Not Applicable
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
 10.958
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12. TYPE OF REPORTING PERSON
 IA
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CUSIP No. 65411N105
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Item 1(a) Name of Issuer:
NIGHTHAWK RADIOLOGY HOLDINGSINC
Item 1(b) Address of Issuer's Principal Executive Offices:
601 FRONT AVE, SUITE 502
COEUR D ALENE ID 83814

Item 2(a) Name of Person(s) Filing:

WATER ISLAND CAPITAL LLC ("WIC")
Item 2(b) Address of Principal Business Office:

41 MADISONAVE SUITE 2802
NEW YORK NY 10010

Item 2(c) Citizenship:
WIC is a Delaware limited liability company.

Item 2(d) Title of Class of Securities:
Common Stock

Item 2(e) CUSIP Number:
65411N105

Item 3 Type of Person:
(e) WIC is an Investment Adviser in accordance with Rule 13d-1(b)(1)(ii)(F).

Item 4 Ownership:
(a) Amount beneficially owned:
 2619660
(b) Percent of class:
 10.958
(c) Number of shares as to which such person has:
(i) Sole power to vote or to direct the vote:
 2619660
(ii) Shared power to vote or to direct the vote:
 None
(iii) Sole power to dispose or direct the disposition of:
 2619660
(iv) Shared power to dispose or direct the disposition of:
 None

Item 5 Ownership of Five Percent or Less of a Class:
 Not Applicable

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:

 WICis an Investment Adviser registered under section 203 of the
 Investment Advisers Act of 1940, as amended.

CUSIP No. 65411N105
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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 acquired and are held in the ordinary course
of business and 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.

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: 12/5/2010

WATER ISLAND CAPITAL LLC

By: /S/ MATTHEW HEMBERGER
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Matthew Hemberger
Chief Financial Officer and Chief Compliance Officer