Sec Form 4/A Filing - ROCKWELL S KENT @ ExOne Co - 2013-02-06

FORM 4/A 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 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

OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5

1. Name and Address of Reporting Person ROCKWELL S KENT 2. Issuer Name and Ticker or Trading Symbol ExOne Co [ XONE] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chair and CEO (Last) (First) (Middle) 127 INDUSTRY BOULEVARD 3. Date of Earliest Transaction (MM/DD/YY) 02/06/2013 (Street) NORTH HUNTINGDON, PA15642 4. If Amendment, Date Original Filed (MM/DD/YY) 02/13/2013 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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 Stock, par value $0.01 02/06/2013( 1 ) C 1,366,694 ( 2 ) A $ 0 5,542,694 I By S. Kent Rockwell Revocable Trust Common Stock, par value $0.01 02/06/2013( 1 ) S 611,667 ( 2 ) D $ 16.74 4,931,027 I By S. Kent Rockwell Revocable Trust

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 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 Class A Preferred Stock $ 0 02/06/2013 C( 4 ) 12,983,602 01/01/2013 02/12/2013 Common Stock, par value $0.01 1,366,694 ( 3 ) $ 0 0 I By S. Kent Rockwell Revocable Trust

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other ROCKWELL S KENT 127 INDUSTRY BOULEVARD NORTH HUNTINGDON, PA15642 X Chair and CEO Signatures /s/ JoEllen Lyons Dillon, attorney-in-fact for S. Kent Rockwell 05/01/2013 Signature of Reporting Person Date

Explanation of Responses:

( 1 )This Form 4 amends the Form 4 filed by Mr. Rockwell on February 13, 2013 to correct the transaction date. ( 2 )S. Kent Rockwell is the beneficiary of the S. Kent Rockwell Revocable Trust, which is the indirect, sole stockholder of Rockwell Forest Products, Inc. and Rockwell Holdings, Inc. which are the record holders of the shares beneficially owned by Mr. Rockwell. This filing includes Rockwell Forest Products as the 10% holder of 4,176,000 shares. Mr. Rockwell disclaims beneficial ownership of the S. Kent Rockwell Revocable Trust, and this report shall not be deemed to be an admission that Mr. Rockwell is the beneficial owner of the securities owned by the S. Kent Rockwell Revocable Trust for purposes of Section 16 or for any other purpose. ( 3 )S. Kent Rockwell is the beneficiary of the S. Kent Rockwell Revocable Trust, which is the indirect, sole stockholder of Rockwell Holdings, Inc. which was the record holder of the preferred shares that were converted into common shares and is the record holder of the resulting common shares. Mr. Rockwell disclaims beneficial ownership of the S. Kent Rockwell Revocable Trust, and this report shall not be deemed to be an admission that Mr. Rockwell is the beneficial owner of the securities owned by the S. Kent Rockwell Revocable Trust for purposes of Section 16 or for any other purpose. ( 4 )This Form 4 amends the Form 4 filed by Mr. Rockwell on February 13, 2013 to correct the transaction codes in columns 4 and 5 of Table II.

Remarks: Exhibit List:Exhibit 24 -Power of Attorney

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* 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).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.