Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Grossack Marshall J
  2. Issuer Name and Ticker or Trading Symbol
Allied World Assurance Co Holdings, AG [AWH]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
EVP, Chief Actuary
(Last)
(First)
(Middle)
ALLIED WORLD ASSURANCE CO. HOLDINGS, AG, GUBELSTRASSE 24, PARK TOWER, 15TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
02/17/2015
(Street)

ZUG, V8 6300
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Shares 02/17/2015   A   9,548 (1) A $ 0 216,260 (2) D  
Common Shares 02/17/2015   F   4,451 (3) D $ 40.24 211,809 D  
Common Shares 02/18/2015   M   876 A $ 0 (4) 212,685 D  
Common Shares 02/18/2015   D   438 D $ 40.4465 (5) 212,247 D  
Common Shares 02/18/2015   F   203 (6) D $ 40.65 212,044 D  
Common Shares 02/19/2015   M   2,208 A $ 0 (7) 214,252 D  
Common Shares 02/19/2015   D   2,208 D $ 40.5293 (8) 212,044 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stock Units (9) 02/17/2015   A   3,050     (10)   (10) Common Shares 3,050 (9) 17,039 (11) (12) D  
Restricted Stock Units (4) 02/18/2015   M     876   (13)   (13) Common Shares 876 (4) 16,163 (11) D  
Restricted Stock Units (7) 02/19/2015   M     2,208   (14)   (14) Common Shares 2,208 (7) 13,955 (11) D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Grossack Marshall J
ALLIED WORLD ASSURANCE CO. HOLDINGS, AG
GUBELSTRASSE 24, PARK TOWER, 15TH FLOOR
ZUG, V8 6300
      EVP, Chief Actuary  

Signatures

 /s/ Wayne H. Datz, by Power of Attorney   02/19/2015
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Represents the Company's common shares that were earned pursuant to a 2012 performance-based award for no monetary consideration and which vested at 136% of target based on the achievement of pre-established performance criteria during the applicable three-year performance period established under the Company's Third Amended and Restated 2004 Stock Incentive Plan.
(2) Includes 294 common shares acquired on December 31, 2014 pursuant to the Company's Amended and Restated 2008 Employee Share Purchase Plan.
(3) Exclusively represents shares withheld by the Company with respect to the payment of withholding tax liability incurred upon the vesting of the performance-based awards.
(4) On February 18, 2014, the reporting person was granted 3,516 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into (i) 1,758 common shares and (ii) cash equal to the market value of 1,758 common shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. These Restricted Stock Units were previously reported as a grant of 1,172 Restricted Stock Units converting into (i) 586 common shares and (ii) cash equal to the market value of 586 common shares. These amounts have been adjusted to reflect the issuer's 3-for-1 stock split paid on May 23, 2014.
(5) The fair market value of the cash portion was determined using the daily volume-weighted average sales price of the common shares for the five consecutive trading days up to and including February 18, 2015.
(6) Exclusively represents shares withheld by the Company with respect to the payment of withholding tax liability incurred upon the vesting of Restricted Stock Units.
(7) On February 19, 2013, the reporting person was granted 8,829 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into cash equal to the market value of 8,829 common shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. These Restricted Stock Units were previously reported as a grant of 2,943 Restricted Stock Units that convert into cash equal to the market value of the 2,943 common shares. The amount has been adjusted to reflect the issuer's 3-for-1 stock split paid on May 23, 2014.
(8) The fair market value was determined using the daily volume-weighted average sales price of the common shares for the five consecutive trading days up to and including February 19, 2015.
(9) Grant of Restricted Stock Units for no monetary consideration. Restricted Stock Units convert into (i) 1,830 common shares and (ii) cash equal to the market value of 1,220 common shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units.
(10) The Restricted Stock Units vest in four equal installments with the first installment vesting on February 17, 2016.
(11) Represents Restricted Stock Units held by the reporting person that vest in whole or in part in cash.
(12) Reflects the issuer's 3-for-1 stock split paid on May 23, 2014.
(13) The Restricted Stock Units vest in four equal installments with the first installment vesting on February 18, 2015.
(14) The Restricted Stock Units vest in four equal installments with the first installment vesting on February 19, 2014.

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