The ExOne Company

127 Industry Boulevard

North Huntingdon, Pennsylvania 15642

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held On May 16, 2018

Dear Stockholder:

You are cordially invited to attend the 2018 Annual Meeting of Stockholders of The ExOne Company (“ExOne” or the “Company”). The meeting will be held on May 16, 2018 at 10:00 a.m., Eastern Daylight Time, at ExOne’s principal executive offices, 127 Industry Boulevard, North Huntingdon, Pennsylvania 15642. At the meeting, holders of ExOne’s issued and outstanding common stock (NASDAQ: XONE) will act upon the following matters:

(1) Election of six (6) nominees to the Board of Directors identified in the accompanying Proxy Statement, each for a term that expires in 2019;

(2) Ratification of the appointment of Schneider Downs & Co., Inc. as ExOne’s independent registered public accounting firm for the year ending December 31, 2018; and

(3) Any other matters that properly come before the meeting.

The record date for the Annual Meeting is March 19, 2018. Only stockholders of record at the close of business on that date are entitled to receive notice of, to attend and to vote at, the Annual Meeting and any postponements or adjournments thereof.

This year, we are pleased to deliver our proxy materials to stockholders primarily over the Internet. Utilizing Internet delivery allows us to distribute our proxy materials in an environmentally responsible and cost-effective manner. On April 5, 2018, we mailed a Notice of Internet Availability of Proxy Materials (the “Internet Notice”) to certain holders of record as of the record date, and posted our proxy materials on the website referenced in the Internet Notice. The Internet Notice explains how to access the proxy materials and the 2017 Annual Report, free of charge, through the website described in the Internet Notice. The Internet Notice and website also provide information regarding how you may request to receive proxy materials in printed form by mail or electronically by email for this meeting and on an ongoing basis.

If you received your Annual Meeting materials by mail, the Proxy Statement, 2017 Annual Report, Notice of Annual Meeting and proxy card were enclosed. Your vote is very important, and we appreciate you taking the time to vote promptly. The proxy card contains instructions on how to vote by proxy by telephone or through the Internet, or you may complete, sign and return the proxy card by mail.

It is very important that your shares are represented at the Annual Meeting, whether or not you plan to attend in person. Accordingly, we request and urge you to review the proxy materials and vote your shares in advance of the meeting. If you decide to attend the Annual Meeting, and wish to vote in person, you may do so by revoking your proxy at that time. Also, if you plan to attend the meeting in person and need directions, please contact the office of the General Counsel and Corporate Secretary at(724) 863-9663. To ensure your vote is counted at the Annual Meeting, please vote as promptly as possible.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR

THE STOCKHOLDER MEETING TO BE HELD ON MAY 16, 2018: OUR PROXY STATEMENT, 2017

ANNUAL REPORT AND NOTICE OF ANNUAL MEETING ARE AVAILABLE WITH YOUR16-DIGIT

CONTROL NUMBER AT

HTTP://WWW.PROXYVOTE.COM.

PROXY SUMMARY

Meeting Information

How to Vote — Your vote is important

Record Date. You are eligible to vote if you were a stockholder of record at the close of business on Monday, March 19, 2018. To make sure that your shares are represented at the meeting, please cast your vote as soon as possible.

Beneficial Owners. If you hold your shares through a broker, bank or other nominee, you will receive voting instructions from your broker, bank or other nominee. Please follow the instructions that you receive to vote your shares.

Registered Owners. If you are a registered holder, please complete and sign the enclosed proxy card and return it to Broadridge by following the instructions on the card. You also may vote your shares by telephone or over the Internet as described on your proxy card.

Online Access to Proxy Materials

The Proxy Statement, 2017 Annual Report and Notice of Annual Meeting are available with your16-digit control number atHTTP://WWW.PROXYVOTE.COM.

Election of Directors

This year, we are recommending the election of six (6) nominees to the Board:

IMPORTANT LETTER FROM THE CHAIRMAN AND CEO KENT ROCKWELL REGARDING OUR INDEPENDENT DIRECTORS AND COMMITTEESName		Age				Independent				Position with ExOne
S. Kent Rockwell			73				No			Executive Chairman
John Irvin			63				No			Director
Gregory F. Pashke			70				Yes			Director and member of Audit Committee and Nominating and Governance Committee
Lloyd A. Semple			78				Yes			Lead Director, Chair of Nominating and Governance Committee and member of Compensation Committee
William F. Strome			63				Yes			Director, Chair of Audit Committee and member of Nominating and Governance Committee and Compensation Committee
Bonnie K. Wachtel			62				Yes			Director, Chair of Compensation Committee and member of Audit Committee

Last year, Institutional Shareholder ServicesFour of the six nominees are “independent” under the NASDAQ Stock Market (“ISS”NASDAQ”) recommendedrules.

TABLE OF CONTENTS

LETTER TO STOCKHOLDERS FROM OUR LEAD DIRECTOR		Page
QUESTIONS AND ANSWERS ABOUT THIS PROXY MATERIAL AND VOTING		1
PROPOSAL 1 — ELECTION OF DIRECTORS		7
EXECUTIVE OFFICERS OF EXONE		13
CORPORATE GOVERNANCE		15
Highlights of Our Corporate Governance Practices		15
Structure and Size of the Board		15
Independence of the Board and Committees		15
Board Leadership Structure and Our Independent Lead Director		16
Risk Oversight Management		16
Information Regarding the Board and its Committees		17
Audit Committee		17
Compensation Committee		17
Compensation Committee Interlocks and Insider Participation		18
Nominating and Governance Committee		19
Director Nomination Process		19
Code of Ethics and Business Conduct		20
Stockholder Communications with the Board		20
Attendance at Annual Meeting of Stockholders by the Board		20
TRANSACTIONS WITH RELATED PERSONS		21
DIRECTOR COMPENSATION		22
COMPENSATION OF NAMED EXECUTIVE OFFICERS		23
Compensation Discussion and Analysis		23
Compensation Committee Report		30
Summary Compensation Table		31
Outstanding Equity Awards at December 31, 2017		32
PROPOSAL 2 —  RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM		34
AUDIT COMMITTEE REPORT		35
AUDIT FEES AND SERVICES		36
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT		38
SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE		39
OTHER MATTERS		40

The ExOne Company

127 Industry Boulevard

North Huntingdon, Pennsylvania 15642

PROXY STATEMENT

FOR THE 2018 ANNUAL MEETING OF STOCKHOLDERS

To Be Held On May 16, 2018 at 10:00 a.m., Eastern Daylight Time

QUESTIONS AND ANSWERS ABOUT THIS PROXY MATERIAL AND VOTING

Why am I receiving these materials?

The Board of Directors (the “Board”) of The ExOne Company (“we,” the “Company,” or “ExOne”) is soliciting your proxy to vote at the 2018 Annual Meeting of Stockholders (the “Annual Meeting”) to be held on May 16, 2018 at 10:00 a.m., Eastern Daylight Time, at ExOne’s principal executive offices, 127 Industry Boulevard, North Huntingdon, Pennsylvania 15642.

You are invited to attend the Annual Meeting to vote on the proposals described in this Proxy Statement. However, you do not need to attend the meeting to vote your shares. If you are a registered holder, you may vote by telephone, over the Internet or by completing, signing and returning a proxy card to Broadridge by following the instructions on the card. If you hold your shares through a broker, bank or other nominee, you will receive voting instructions from your broker, bank or other nominee. Please follow the instructions that you receive to vote your shares.

We intend to mail to all stockholders of record entitled to vote at the Annual Meeting either the Internet Notice or a full set paper copy of this Proxy Statement, together with our 2017 Annual Report, the Notice of Annual Meeting and the accompanying proxy card on or about April 5, 2018.

Copies of our 2017 Annual Report furnished to our stockholders do not contain copies of exhibits to our Annual Report on Form10-K for the year ended December 31, 2017. You can obtain copies of these exhibits electronically at the website of the Securities and Exchange Commission (the “SEC”) atwww.sec.gov or by mail from the Public Reference Section of the SEC at 100 F Street, N.E., Washington, D.C. 20549 at prescribed rates. The exhibits are also available as part of theForm 10-K for the year ended December 31, 2017 which is available on ExOne’s corporate website atwww.exone.com. Stockholders may also obtain copies of exhibits without charge by contacting our General Counsel and Corporate Secretary at(724) 863-9663.

We will also post this Proxy Statement, our 2017 Annual Report and the Notice of Annual Meeting on the Internet atHTTP://WWW.PROXYVOTE.COM on or about April 5, 2018, which you may access using your16-digit control number.

Why did I receive an Internet Notice in the mail regarding the Internet availability of proxy materials instead of a full set paper copy of this Proxy Statement, the 2017 Annual Report and the Notice of Annual Meeting?

We are taking advantage of an SEC rule that allows companies to furnish their proxy materials over the Internet rather than in paper form. This rule allows a company to send some or all of its stockholders the Internet Notice. Instructions on how to access the proxy materials over the Internet or how to request a paper copy of proxy materials may be found in the Internet Notice.

If you would prefer to receive proxy materials (including a proxy card) in printed form by mail or electronically by email, please follow the instructions contained in the Internet Notice.

Why didn’t I receive an Internet Notice in the mail regarding the Internet availability of proxy materials?

The SEC rule that allows us to furnish our proxy materials over the Internet rather than in paper form does not require us to do so for all stockholders. We may choose to send certain stockholders the Internet Notice, while sending other stockholders a full set paper copy of our Proxy Statement, 2017 Annual Report, Notice of Annual Meeting and proxy card.

Who can vote at the Annual Meeting and when is the Record Date?

Only stockholders of record at the close of business on March 19, 2018 are entitled to vote at the Annual Meeting. On the record date, there were 16,202,119 shares of ExOne common stock (“Common Stock”) outstanding. All holders of these outstanding shares are entitled to one vote for each share of Common Stock held by them as of the close of business on March 19, 2018 for each matter to be voted on at the Annual Meeting.

How can I access the proxy materials over the Internet?

An electronic copy of this Proxy Statement, the 2017 Annual Report and the Notice of Annual Meeting are available with your16-digit control number atHTTP://WWW.PROXYVOTE.COM.

What proposals are being considered?

There are two matters scheduled for a vote at the Annual Meeting:

How do I vote?

For Proposal No. 1, you may vote“For” or“Against” each director nominee or you may“Abstain” from voting for any nominee. For Proposal No. 2, you may vote“For” or“Against” the proposal or“Abstain” from voting.

Stockholder of Record (Shares Registered in Your Name) —If on March 19, 2018, your shares were registered directly in your name with ExOne’s transfer agent, American Stock Transfer & Trust, LLP, then you are a stockholder of record with respect to those shares.

As a stockholder of record, you may vote by proxy by telephone, over the Lead Director,Internet or by returning a proxy card, or you may vote in person at the Annual Meeting. Regardless of whether you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting and vote in person if you have already voted by proxy.

Beneficial Owner (Shares Registered in the Name of a Broker, Bank or Other Nominee) — If on March 19, 2018, your shares were held in an account at a broker, bank, or other similar organization as your

nominee, then you are the beneficial owner of shares held in “street name” and these proxy materials are being forwarded to you by that organization. The organization holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting.

As a beneficial owner, you have the right to direct that organization on how to vote the shares in your account. Please refer to the voting instructions provided by your broker, bank or other nominee. Many organizations allow beneficial owners to give voting instructions via telephone or the Internet, as well as in writing. You also are invited to attend the Annual Meeting, but you will need to bring a copy of a brokerage statement reflecting stock ownership as of March 19, 2018. Because you are not the stockholder of record, you may not vote your shares in person at the meeting unless you provide a valid proxy (sometimes referred to as a “legal proxy”) from your broker, bank or other nominee.

How many votes do I have?

You have one vote for each share of Common Stock you own as of the close of business on March 19, 2018 for each matter to be voted on at the Annual Meeting. You may vote on each proposal presented for consideration at the Annual Meeting. There are no cumulative voting rights with respect to our Common Stock.

What if I return a proxy card but do not make specific choices?

If you return a signed and dated proxy card without marking any voting selections, your shares will be voted“For” the election of each of the six (6) nominees for director, and“For” ratification of Schneider Downs & Co., Inc. as our independent registered public accounting firm for the year ending December 31, 2018. If any other matter is properly presented at the meeting, your proxy (one of the individuals named on your proxy card) will vote your shares using his or her best judgment.

What do I need to do to attend the Annual Meeting in person?

Space for the Annual Meeting is limited. Therefore, admission will be on a first-come, first-served basis. Registration will open at 9:45 a.m. Eastern Daylight Time, and the Annual Meeting will begin at 10:00 a.m. Each stockholder should be prepared to present:

Use of cameras, recording devices, computers and other electronic devices, such as smart phones and tablets, are not permitted at the Annual Meeting. Photography and video are prohibited at the Annual Meeting.

Please allow ample time forcheck-in. Please note that large bags and packages are not allowed at the Annual Meeting. Persons may be subject to search.

Who is paying for this proxy solicitation?

ExOne will pay for the entire cost of soliciting proxies. In addition to ExOne mailing these proxy materials, ExOne’s directors and employees also may solicit proxies in person, by telephone, or by other means of communication. Directors and employees will not be paid any additional compensation for soliciting proxies. ExOne may reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one set of proxy materials?

If you receive more than one set of proxy materials (including multiple Internet Notices or multiple copies of this Proxy Statement, Notice of Annual Meeting and proxy card), your shares are registered in more than one name or are registered in different accounts. Please make sure that you vote all of your shares by following the directions on each Internet Notice or proxy card.

Can I change my rolevote after submitting my proxy?

Yes. You can change your vote at any time before the final vote at the meeting.

If you are a stockholder of record, you may change your vote in any one of the following ways:

If you are a beneficial owner of shares held in street name, you may change your vote in any one of the following ways:

How are votes counted?

We have designated a representative of Broadridge Financial Services as the inspector of elections who will validate the votes.

With respect to Proposal No. 1, the inspector of elections will count“For” votes and“Against” votes. Abstentions and brokernon-votes will not be counted as having been voted on the proposal, nor will they affect the outcome of Proposal No. 1.

With respect to Proposal No. 2, the inspector of elections will count separately“For,” “Against” and“Abstain” votes and brokernon-votes.“Abstain” votes will be counted towards the vote total for the proposal, and will have the same effect as“Against” votes. Because brokernon-votes are not deemed to be votes entitled to be cast, they will not affect the outcome of Proposal No. 2.

See “How many votes are needed to approve each proposal?” for further details regarding the votes needed to approve each proposal.

What is a “brokernon-vote”?

If your shares are held by your broker, bank or other similar organization as your nominee (that is, in “street name”), you will need to work closelyfollow the voting instructions provided by that organization on how to vote your shares. If you do not provide voting instructions, your shares may constitute “brokernon-votes.” Generally, brokernon-votes occur on a matter when a broker, bank or other nominee is not permitted to vote on that matter, including the election of directors, without instructions from the beneficial owner and instructions are not given.

In tabulating the voting result for any particular proposal, shares that constitute brokernon-votes are not considered entitled to vote on that proposal. Thus, while brokernon-votes will be counted as present for the purpose of determining the presence of a quorum at the meeting, brokernon-votes willnot affect the outcome of any matter being voted on at the meeting.

How many votes are needed to approve each proposal?

Proposal No. 1. Directors will be elected by the vote of a majority of the shares cast with Chairmanrespect to the director at the Annual Meeting. This means that the number of votes cast“For” a director’s election must exceed the number of votes cast“Against” that director’s election. Stockholders may not cumulate votes in the election of directors. Abstentions and CEO Kent Rockwellbrokernon-votes will not be counted as having been voted on the proposal, nor will they affect the outcome of this proposal.

Proposal No. 2. Ratification of the appointment of Schneider Downs & Co., Inc. as ExOne’s independent registered public accounting firm for the year ending December 31, 2018 requires the affirmative vote of a majority of the shares represented at the Annual Meeting and entitled to provide strong leadershipvote on this matter. Abstentions will have the same effect as an“Against” vote. Because brokernon-votes are not deemed to be votes entitled to be cast, they will not affect the outcome of this proposal.

What are the Board’s voting recommendations?

What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if a majority of all outstanding shares entitled to vote is represented by stockholders present at the meeting or represented by proxy. On the record date, there were 16,202,119 shares of Common Stock outstanding and entitled to vote. This means that at least 8,101,060 shares must be represented by stockholders present at the meeting or represented by proxy to have a quorum. Your shares will be counted towards the quorum if you submit a valid proxy or vote at the meeting.

How can I find out the results of the voting at the Annual Meeting?

Preliminary voting results will be announced at the Annual Meeting. Final voting results will be published in a Current Report onForm 8-K filed with the SEC within four business days following the Annual Meeting. In the event we are unable to obtain the final voting results within four business days, we will file the preliminary voting results in a Current Report onForm 8-K within four business days following the Annual Meeting, and will file an amended Current Report onForm 8-K with the final voting results within four business days after the final voting results are known.

How can stockholders submit a proposal for inclusion in our Proxy Statement for the 2019 Annual Meeting of Stockholders?

Our 2019 Annual Meeting of Stockholders will be held on May 15, 2019 at 10:00 a.m. To be included in our Proxy Statement for the 2019 Annual Meeting of Stockholders, stockholder proposals must comply with the requirements ofRule 14a-8 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). To be eligible for inclusion, such proposals must be received by ExOne by December 6, 2018, which is at least 120 calendar days before the anniversary date of the release of ExOne’s Proxy Statement to stockholders in connection with the previous year’s annual meeting.

How can stockholders submit nominations of persons for election to the Board or proposals of business to be transacted by the stockholders for the 2019 Annual Meeting of Stockholders?

A stockholder of record may submit nominations of persons for election to the Board or proposals of business to be transacted by the stockholders only if he or she complies with Article III, Section 13 of our Amended and Restated Bylaws, as amended (the “Bylaws”). This section provides that a stockholder must give advance notice to our Corporate Secretary of any business, including nominations of directors for our Board, that the stockholder wishes to raise at the 2019 Annual Meeting of Stockholders at our principal executive offices (i) not earlier than 120 days prior to such meeting and (ii) at least 45 days prior to the anniversary date of the filing of ExOne’s Proxy Statement with the SEC in connection with the previous year’s annual meeting. Therefore, for the 2019 Annual Meeting, such notice must be received by ExOne no sooner than January 15, 2019 and no later than February 19, 2019.

With respect to a stockholder’s nomination of a candidate for our Board, the stockholder notice to our Corporate Secretary must contain certain information as set forth in our Bylaws about both the nominee and the Company. I welcome this opportunitystockholder making the nomination. With respect to communicate with you as ExOne stockholders.

ExOne is working hard to achieve long-term, sustainable operating and financial performance. We are striving to create value throughany other business that the rightstockholder proposes, the stockholder notice must contain a brief description of such business, strategies, effective corporate governance and executive compensation programs and well-functioning talent and succession planning. The Board oversees these efforts and wants to set the right tonereasons for conducting such business at the top. Wemeeting, any personal or other direct or indirect material interest in such business of such stockholder and the beneficial owner, if any, on whose behalf the proposal is made, and certain other information specified in our Bylaws.

If you wish to bring a stockholder proposal or nominate a candidate for director, you are committedadvised to creatingreview our Bylaws, which contain additional requirements about advance notice of stockholder proposals and director nominations.

If a culture that promotesstockholder wishes only to recommend a candidate for consideration by the Nominating and values performance, integrity, ethics andGovernance Committee as a long-term view aligned withpotential nominee for director, see the interests of our stockholders.

Performance and Strategy

In 2014, ExOne made important progress but fell short of its goals. The Company achieved $43.9 millionprocedures discussed in revenues driven by 45% growth in global non-machine revenue. It is the Board’s responsibility to ensure that management addresses performance and strategy, and, in response, the Board formed a Strategic Oversight Committee to oversee ExOne’s strategies.

“

PROXY SUMMARY

Meeting Information

How to Vote — Your vote is important

Record Date. You are eligible to vote if you were a stockholder of record at the close of business on Monday, March 19, 2018. To make sure that your shares are represented at the meeting, please cast your vote as soon as possible.

Beneficial Owners. If you hold your shares through a broker, bank or other nominee, you will receive voting instructions from your broker, bank or other nominee. Please follow the instructions that you receive to vote your shares.

Registered Owners. If you are a registered holder, please complete and sign the enclosed proxy card and return it to Broadridge by following the instructions on the card. You also may vote your shares by telephone or over the Internet as described on your proxy card.

Online Access to Proxy Materials

The Proxy Statement, 2017 Annual Report and Notice of Annual Meeting are available with your16-digit control number atHTTP://WWW.PROXYVOTE.COM.

Election of Directors

This year, we are recommending the election of six (6) nominees to the Board:

Four of the six nominees are “independent” under the NASDAQ Stock Market (“NASDAQ”) rules.

TABLE OF CONTENTS

In 2015, we will continue to consider corporate governance measures that are right for our Company and stockholders.

Executive Compensation

ExOne’s compensation is performance driven. In 2013 we adopted an equity incentive compensation plan. However, the Compensation Committee did not formalize an incentive based program for executives for 2014 for two reasons. First, we are a small emerging growth company. More importantly, four out of five members of our executive team already have significant ownership in the Company having invested their own money in ExOne before or in connection with our initial public offering (“IPO”). In fact, Chairman and Chief Executive Officer Kent Rockwell is ExOne’s largest beneficial owner. We believe that this ownership provides a strong foundation of alignment between ExOne stockholders and our management team.

In addressing compensation decisions for 2014, the Compensation Committee weighed ExOne’s 2014 performance. Our Chief Executive Officer received minimal compensation above his base salary. In December 2014, our President and Chief Operating Officer stepped down from that role to another position within the Company. No executive received a discretionary cash bonus for 2014, although several executives received an equity grant with three-year vesting to reward individual performance and also to maintain long-term stockholder focus. The Board also adopted a stock retention policy in early 2015 that applies to equity awards made to directors and executive officers to further align the interests of stockholders and ExOne directors and executives.

Addressing the material weaknesses in our internal controls

As part of the 2013 IPO process, ExOne identified material weaknesses in its internal controls over financial reporting. Remediation of these weaknesses is a top priority for our Audit Committee, Board and management. However, this is a complex project that takes time to complete correctly. Our Audit Committee, which is composed of highly qualified, independent individuals, oversees this project. Since the IPO, our Audit Committee has met 15 times with remediation of material weaknesses in internal controls over financial reporting as a standing agenda item in 2014.

With the oversight of the Audit Committee, ExOne identified and engaged a consultant to assess alternative systems and choose an enterprise resource planning (“ERP”) system provider. In February 2014 ExOne engaged proALPHA, an ERP system provider based in Germany. Since then ExOne has been implementing an ERP system with proALPHA’s help. The first phase of the implementation went live on January 5, 2015 and included certain modules of the ERP system implemented in our European operations. ExOne has also been working to redesign processes to improve controls over financial reporting and to implement other information technology improvements at the same time that the ERP system is being implemented.

Since the IPO, ExOne has also added substantial accounting and financial reporting talent by hiring a Chief Accounting Officer, a new Chief Financial Officer, a Director of Internal Audit and Controls, a Director of Information Systems and Reporting, a Senior Accountant in the United States and a Senior Accountant in Germany.

These ongoing efforts, collectively, give ExOne the opportunity to remediate the material weaknesses in internal controls when ExOne reports its results for the 2015 fiscal year.

Our Board

Our Board continues to evolve and is comprised of a group of highly capable and diverse directors who are well-equipped to oversee the success of ExOne’s business and effectively represent your interests as stockholders. I encourage you to review the qualifications, skills and experience that we have identified as important attributes for our directors in the Proxy Statement.

Please review the information in the Proxy Statement and in ExOne’s 2014 Annual Report for more information on ExOne. I hope that you will continue to share your thoughts or concerns with the Board on any topic. Communications can be addressed to The Board of Directors, c/o Chief Legal Officer and Corporate Secretary, The ExOne Company, 127 Industry Boulevard, North Huntingdon, PA 15642.

We value your input, your investment and your support. Thank you.

Sincerely,

LLOYD A. SEMPLE

Lead Director

The ExOne Company

127 Industry Boulevard

North Huntingdon, Pennsylvania 15642

NOTICE OFPROXY STATEMENT

FOR THE 2018 ANNUAL MEETING OF STOCKHOLDERS

To Be Held On May 4, 201516, 2018 at 10:00 a.m., Eastern Daylight Time

Dear Stockholder:QUESTIONS AND ANSWERS ABOUT THIS PROXY MATERIAL AND VOTING

You are cordially invitedWhy am I receiving these materials?

The Board of Directors (the “Board”) of The ExOne Company (“we,” the “Company,” or “ExOne”) is soliciting your proxy to attendvote at the 20152018 Annual Meeting of Stockholders of The ExOne Company (“ExOne”(the “Annual Meeting”). The meeting will to be held on May 4, 201516, 2018 at 10:00 a.m., Eastern Daylight Time, at ExOne’s principal executive offices, 127 Industry Boulevard, North Huntingdon, Pennsylvania 15642.

You are invited to attend the Westin Convention Center Pittsburgh, located at 1000 Penn Avenue, Pittsburgh, Pennsylvania 15222. AtAnnual Meeting to vote on the proposals described in this Proxy Statement. However, you do not need to attend the meeting to vote your shares. If you are a registered holder, you may vote by telephone, over the Internet or by completing, signing and returning a proxy card to Broadridge by following the instructions on the card. If you hold your shares through a broker, bank or other nominee, you will receive voting instructions from your broker, bank or other nominee. Please follow the instructions that you receive to vote your shares.

We intend to mail to all stockholders of record entitled to vote at the Annual Meeting either the Internet Notice or a full set paper copy of this Proxy Statement, together with our 2017 Annual Report, the Notice of Annual Meeting and the accompanying proxy card on or about April 5, 2018.

Copies of our 2017 Annual Report furnished to our stockholders do not contain copies of exhibits to our Annual Report on Form10-K for the year ended December 31, 2017. You can obtain copies of these exhibits electronically at the website of the Securities and Exchange Commission (the “SEC”) atwww.sec.gov or by mail from the Public Reference Section of the SEC at 100 F Street, N.E., Washington, D.C. 20549 at prescribed rates. The exhibits are also available as part of theForm 10-K for the year ended December 31, 2017 which is available on ExOne’s corporate website atwww.exone.com. Stockholders may also obtain copies of exhibits without charge by contacting our General Counsel and Corporate Secretary at(724) 863-9663.

We will also post this Proxy Statement, our 2017 Annual Report and the Notice of Annual Meeting on the Internet atHTTP://WWW.PROXYVOTE.COM on or about April 5, 2018, which you may access using your16-digit control number.

Why did I receive an Internet Notice in the mail regarding the Internet availability of proxy materials instead of a full set paper copy of this Proxy Statement, the 2017 Annual Report and the Notice of Annual Meeting?

We are taking advantage of an SEC rule that allows companies to furnish their proxy materials over the Internet rather than in paper form. This rule allows a company to send some or all of its stockholders the Internet Notice. Instructions on how to access the proxy materials over the Internet or how to request a paper copy of proxy materials may be found in the Internet Notice.

If you would prefer to receive proxy materials (including a proxy card) in printed form by mail or electronically by email, please follow the instructions contained in the Internet Notice.

Why didn’t I receive an Internet Notice in the mail regarding the Internet availability of proxy materials?

The SEC rule that allows us to furnish our proxy materials over the Internet rather than in paper form does not require us to do so for all stockholders. We may choose to send certain stockholders the Internet Notice, while sending other stockholders a full set paper copy of our Proxy Statement, 2017 Annual Report, Notice of Annual Meeting and proxy card.

Who can vote at the Annual Meeting and when is the Record Date?

Only stockholders of record at the close of business on March 19, 2018 are entitled to vote at the Annual Meeting. On the record date, there were 16,202,119 shares of ExOne common stock (“Common Stock”) outstanding. All holders of these outstanding shares are entitled to one vote for each share of Common Stock held by them as of the close of business on March 19, 2018 for each matter to be voted on at the Annual Meeting.

How can I access the proxy materials over the Internet?

An electronic copy of this Proxy Statement, the 2017 Annual Report and the Notice of Annual Meeting are available with your16-digit control number atHTTP://WWW.PROXYVOTE.COM.

What proposals are being considered?

There are two matters scheduled for a vote at the Annual Meeting:

How do I vote?

For Proposal No. 1, you may vote“For” or“Against” each director nominee or you may“Abstain” from voting for any nominee. For Proposal No. 2, you may vote“For” or“Against” the proposal or“Abstain” from voting.

Stockholder of Record (Shares Registered in Your Name) —If on March 19, 2018, your shares were registered directly in your name with ExOne’s issuedtransfer agent, American Stock Transfer & Trust, LLP, then you are a stockholder of record with respect to those shares.

As a stockholder of record, you may vote by proxy by telephone, over the Internet or by returning a proxy card, or you may vote in person at the Annual Meeting. Regardless of whether you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting and outstanding commonvote in person if you have already voted by proxy.

Beneficial Owner (Shares Registered in the Name of a Broker, Bank or Other Nominee) — If on March 19, 2018, your shares were held in an account at a broker, bank, or other similar organization as your

nominee, then you are the beneficial owner of shares held in “street name” and these proxy materials are being forwarded to you by that organization. The organization holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting.

As a beneficial owner, you have the right to direct that organization on how to vote the shares in your account. Please refer to the voting instructions provided by your broker, bank or other nominee. Many organizations allow beneficial owners to give voting instructions via telephone or the Internet, as well as in writing. You also are invited to attend the Annual Meeting, but you will need to bring a copy of a brokerage statement reflecting stock (NASDAQ: XONE)ownership as of March 19, 2018. Because you are not the stockholder of record, you may not vote your shares in person at the meeting unless you provide a valid proxy (sometimes referred to as a “legal proxy”) from your broker, bank or other nominee.

How many votes do I have?

You have one vote for each share of Common Stock you own as of the close of business on March 19, 2018 for each matter to be voted on at the Annual Meeting. You may vote on each proposal presented for consideration at the Annual Meeting. There are no cumulative voting rights with respect to our Common Stock.

What if I return a proxy card but do not make specific choices?

If you return a signed and dated proxy card without marking any voting selections, your shares will act uponbe voted“For” the election of each of the six (6) nominees for director, and“For” ratification of Schneider Downs & Co., Inc. as our independent registered public accounting firm for the year ending December 31, 2018. If any other matter is properly presented at the meeting, your proxy (one of the individuals named on your proxy card) will vote your shares using his or her best judgment.

What do I need to do to attend the Annual Meeting in person?

Space for the Annual Meeting is limited. Therefore, admission will be on a first-come, first-served basis. Registration will open at 9:45 a.m. Eastern Daylight Time, and the Annual Meeting will begin at 10:00 a.m. Each stockholder should be prepared to present:

Use of cameras, recording devices, computers and other electronic devices, such as smart phones and tablets, are not permitted at the Annual Meeting. Photography and video are prohibited at the Annual Meeting.

Please allow ample time forcheck-in. Please note that large bags and packages are not allowed at the Annual Meeting. Persons may be subject to search.

Who is paying for this proxy solicitation?

ExOne will pay for the entire cost of soliciting proxies. In addition to ExOne mailing these proxy materials, ExOne’s directors and employees also may solicit proxies in person, by telephone, or by other means of communication. Directors and employees will not be paid any additional compensation for soliciting proxies. ExOne may reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one set of proxy materials?

If you receive more than one set of proxy materials (including multiple Internet Notices or multiple copies of this Proxy Statement, Notice of Annual Meeting and proxy card), your shares are registered in more than one name or are registered in different accounts. Please make sure that you vote all of your shares by following the directions on each Internet Notice or proxy card.

Can I change my vote after submitting my proxy?

Yes. You can change your vote at any time before the final vote at the meeting.

If you are a stockholder of record, you may change your vote in any one of the following matters:ways:

(1) Election

If you are a beneficial owner of seven (7) nomineesshares held in street name, you may change your vote in any one of the following ways:

How are votes counted?

We have designated a representative of Broadridge Financial Services as the inspector of elections who will validate the votes.

With respect to Proposal No. 1, the inspector of elections will count“For” votes and“Against” votes. Abstentions and brokernon-votes will not be counted as having been voted on the proposal, nor will they affect the outcome of Proposal No. 1.

With respect to Proposal No. 2, the inspector of elections will count separately“For,” “Against” and“Abstain” votes and brokernon-votes.“Abstain” votes will be counted towards the vote total for the proposal, and will have the same effect as“Against” votes. Because brokernon-votes are not deemed to be votes entitled to be cast, they will not affect the outcome of Proposal No. 2.

See “How many votes are needed to approve each proposal?” for further details regarding the votes needed to approve each proposal.

What is a “brokernon-vote”?

If your shares are held by your broker, bank or other similar organization as your nominee (that is, in “street name”), you will need to follow the voting instructions provided by that organization on how to vote your shares. If you do not provide voting instructions, your shares may constitute “brokernon-votes.” Generally, brokernon-votes occur on a matter when a broker, bank or other nominee is not permitted to vote on that matter, including the election of directors, without instructions from the beneficial owner and instructions are not given.

In tabulating the voting result for any particular proposal, shares that constitute brokernon-votes are not considered entitled to vote on that proposal. Thus, while brokernon-votes will be counted as present for the purpose of determining the presence of a quorum at the meeting, brokernon-votes willnot affect the outcome of any matter being voted on at the meeting.

How many votes are needed to approve each proposal?

Proposal No. 1. Directors will be elected by the vote of a majority of the shares cast with respect to the Boarddirector at the Annual Meeting. This means that the number of Directors identifiedvotes cast“For” a director’s election must exceed the number of votes cast“Against” that director’s election. Stockholders may not cumulate votes in the accompanying Proxy Statement, each for a term that expires in 2016;election of directors. Abstentions and brokernon-votes will not be counted as having been voted on the proposal, nor will they affect the outcome of this proposal.

(2)Proposal No. 2. Ratification of the appointment of Baker Tilly Virchow Krause, LLPSchneider Downs & Co., Inc. as ExOne’s independent registered public accounting firm for the year ending December 31, 2015; and

(3) Any other matters that properly come before2018 requires the meeting.

Details regardingaffirmative vote of a majority of the business to be conducted at the Annual Meeting are described in the Proxy Statement accompanying this Notice.

The record date for the 2015 Annual Meeting is March 6, 2015. Only stockholders of record at the close of business on that date are entitled to receive notice of, to attend and to voteshares represented at the Annual Meeting and entitled to vote on this matter. Abstentions will have the same effect as an“Against” vote. Because brokernon-votes are not deemed to be votes entitled to be cast, they will not affect the outcome of this proposal.

What are the Board’s voting recommendations?

What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if a majority of all outstanding shares entitled to vote is represented by stockholders present at the meeting or represented by proxy. On the record date, there were 16,202,119 shares of Common Stock outstanding and entitled to vote. This means that at least 8,101,060 shares must be represented by stockholders present at the meeting or represented by proxy to have a quorum. Your shares will be counted towards the quorum if you submit a valid proxy or vote at the meeting.

How can I find out the results of the voting at the Annual Meeting?

Preliminary voting results will be announced at the Annual Meeting. Final voting results will be published in a Current Report onForm 8-K filed with the SEC within four business days following the Annual Meeting. In the event we are unable to obtain the final voting results within four business days, we will file the preliminary voting results in a Current Report onForm 8-K within four business days following the Annual Meeting, and will file an amended Current Report onForm 8-K with the final voting results within four business days after the final voting results are known.

How can stockholders submit a proposal for inclusion in our Proxy Statement for the 2019 Annual Meeting of Stockholders?

Our 2019 Annual Meeting of Stockholders will be held on May 15, 2019 at 10:00 a.m. To be included in our Proxy Statement for the 2019 Annual Meeting of Stockholders, stockholder proposals must comply with the requirements ofRule 14a-8 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). To be eligible for inclusion, such proposals must be received by ExOne by December 6, 2018, which is at least 120 calendar days before the anniversary date of the release of ExOne’s Proxy Statement to stockholders in connection with the previous year’s annual meeting.

How can stockholders submit nominations of persons for election to the Board or proposals of business to be transacted by the stockholders for the 2019 Annual Meeting of Stockholders?

A stockholder of record may submit nominations of persons for election to the Board or proposals of business to be transacted by the stockholders only if he or she complies with Article III, Section 13 of our Amended and Restated Bylaws, as amended (the “Bylaws”). This section provides that a stockholder must give advance notice to our Corporate Secretary of any postponementsbusiness, including nominations of directors for our Board, that the stockholder wishes to raise at the 2019 Annual Meeting of Stockholders at our principal executive offices (i) not earlier than 120 days prior to such meeting and (ii) at least 45 days prior to the anniversary date of the filing of ExOne’s Proxy Statement with the SEC in connection with the previous year’s annual meeting. Therefore, for the 2019 Annual Meeting, such notice must be received by ExOne no sooner than January 15, 2019 and no later than February 19, 2019.

With respect to a stockholder’s nomination of a candidate for our Board, the stockholder notice to our Corporate Secretary must contain certain information as set forth in our Bylaws about both the nominee and the stockholder making the nomination. With respect to any other business that the stockholder proposes, the stockholder notice must contain a brief description of such business, the reasons for conducting such business at the meeting, any personal or adjournments thereof.other direct or indirect material interest in such business of such stockholder and the beneficial owner, if any, on whose behalf the proposal is made, and certain other information specified in our Bylaws.

If you wish to attend the meeting to vote in person and need directions, please contact the office of the Chief Legal Officer and Corporate Secretary at (724) 863-9663. To ensure that your vote is counted at the Annual Meeting, please vote as promptly as possible. Ifbring a stockholder proposal or nominate a candidate for director, you are a registered holder, please complete, signadvised to review our Bylaws, which contain additional requirements about advance notice of stockholder proposals and date the enclosed proxy card and return it promptly in the enclosed envelope. If you hold your shares through a broker or bank, you will receive voting instructions from your broker or bank. Please follow the instructions that you receive to vote your shares.

IMPORTANT NOTICE REGARDING AVAILABILITY OF PROXY MATERIALS FORdirector nominations.

STOCKHOLDERS MEETING TO BE HELD ON MAY 4, 2015: OUR 2015 PROXY STATEMENT, 2014

ANNUAL REPORT AND FORM OF PROXY CARD ARE AVAILABLE ATHTTP://WWW.ASTPROXYPORTAL.COM/AST/18123/.

The ExOne Company

127 Industry Boulevard

North Huntingdon, Pennsylvania 15642

PROXY STATEMENT

FOR THE 20152018 ANNUAL MEETING OF STOCKHOLDERS

To Be Held On May 4, 201516, 2018 at 10:00 a.m., Eastern Daylight Time

QUESTIONS AND ANSWERS ABOUT THIS PROXY MATERIAL AND VOTING

Why am I receiving these materials?

The Board of Directors (the “Board”) of The ExOne Company (“we,” the “Company,” or “ExOne”) is soliciting your proxy to vote at the 20152018 Annual Meeting of Stockholders (the “Annual Meeting”) to be held on May 4, 201516, 2018 at 10:00 a.m., Eastern Daylight Time, at the Westin Convention Center Pittsburgh, 1000 Penn Avenue, Pittsburgh,ExOne’s principal executive offices, 127 Industry Boulevard, North Huntingdon, Pennsylvania 15222.15642.

You are invited to attend the Annual Meeting to vote on the proposals described in this Proxy Statement. However, you do not need to attend the meeting to vote your shares. If you are a registered holder, you may vote by telephone, over the Internet or by completing, signing and returning a proxy card to us at 127 Industry Boulevard, North Huntingdon, Pennsylvania 15642.Broadridge by following the instructions on the card. If you hold your shares through a broker, bank or bank,other nominee, you will receive voting instructions from your broker, bank or bank.other nominee. Please follow the instructions that you receive to vote your shares.

We intend to commence mailingmail to all stockholders of record entitled to vote at the Annual Meeting either the Internet Notice or a full set paper copy of this Proxy Statement, together with our 2017 Annual Report, on Form 10-K for the year ended December 31, 2014, the Notice of Annual Meeting and the accompanying proxy card on or about April 2, 2015.5, 2018.

Copies of our 2017 Annual Report furnished to our stockholders do not contain copies of exhibits to our Annual Report on Form10-K for the year ended December 31, 2017. You can obtain copies of these exhibits electronically at the website of the Securities and Exchange Commission (the “SEC”) atwww.sec.gov or by mail from the Public Reference Section of the SEC at 100 F Street, N.E., Washington, D.C. 20549 at prescribed rates. The exhibits are also available as part of theForm 10-K for the year ended December 31, 2017 which is available on ExOne’s corporate website atwww.exone.com. Stockholders may also obtain copies of exhibits without charge by contacting our General Counsel and Corporate Secretary at(724) 863-9663.

We will also post this Proxy Statement, the proxy card and our 20142017 Annual Report and the Notice of Annual Meeting on the Internet at:atHTTP://WWW.ASTPROXYPORTAL.COM/AST/18123/WWW.PROXYVOTE.COM on or about April 2, 2015.5, 2018, which you may access using your16-digit control number.

Why did I receive an Internet Notice in the mail regarding the Internet availability of proxy materials instead of a full set paper copy of this Proxy Statement, the 2017 Annual Report and the Notice of Annual Meeting?

We are taking advantage of an SEC rule that allows companies to furnish their proxy materials over the Internet rather than in paper form. This rule allows a company to send some or all of its stockholders the Internet Notice. Instructions on how to access the proxy materials over the Internet or how to request a paper copy of proxy materials may be found in the Internet Notice.

If you would prefer to receive proxy materials (including a proxy card) in printed form by mail or electronically by email, please follow the instructions contained in the Internet Notice.

Why didn’t I receive an Internet Notice in the mail regarding the Internet availability of proxy materials?

The SEC rule that allows us to furnish our proxy materials over the Internet rather than in paper form does not require us to do so for all stockholders. We may choose to send certain stockholders the Internet Notice, while sending other stockholders a full set paper copy of our Proxy Statement, 2017 Annual Report, Notice of Annual Meeting and proxy card.

Who can vote at the Annual Meeting and when is the Record Date?

Only stockholders of record at the close of business on March 6, 201519, 2018 are entitled to vote at the Annual Meeting. On the record date, there were 14,516,13716,202,119 shares of ExOne common stock (“Common Stock”) outstanding. All holders of these outstanding shares are entitled to one vote for each share of Common Stock held by them as of the close of business on March 6, 201519, 2018 for each matter to be voted on at the Annual Meeting.

How can I access the proxy materials over the Internet?

The enclosed proxy card contains instructions on how to view the proxy materials on the Internet. An electronic copy of this Proxy Statement, the 2017 Annual Report and the 2014Notice of Annual ReportMeeting are available with your16-digit control number atHTTP://WWW.ASTPROXYPORTAL.COM/AST/18123/WWW.PROXYVOTE.COM.

What proposals are being considered?

There are two matters scheduled for a vote at the Annual Meeting:

•

Proposal No. 2: Ratification of the appointment of Baker Tilly Virchow Krause, LLPSchneider Downs & Co., Inc. as ExOne’s independent registered public accounting firm for the year ending December 31, 2015.2018.

How do I vote?

For Proposal No. 1, you may vote“For” or“Against” each director nominee or you may“Abstain” from voting for any nominee. For Proposal No. 2, you may vote“For”or“Against” the proposal or“Abstain” from voting.

Stockholder of Record (Shares Registered in Your Name) – —If on March 6, 2015,19, 2018, your shares were registered directly in your name with ExOne’s transfer agent, American Stock Transfer & Trust, LLP, then you are a stockholder of record with respect to those shares.

As a stockholder of record, you may vote by proxy usingby telephone, over the Internet or by returning a proxy card, or you may vote in person at the Annual Meeting. Regardless of whether you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting and vote in person if you have already voted by proxy.

Beneficial Owner (Shares Registered in the Name of a Broker, Bank or Bank) –Other Nominee) —If on March 6, 2015,19, 2018, your shares were held in an account at a broker, bank, or other similar organization as your

nominee, then you are the beneficial owner of shares held in “street name” and these proxy materials are being forwarded to you by that organization. The organization holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting.

As a beneficial owner, you have the right to direct that organization on how to vote the shares in your account. Please refer to the voting instructions provided by your broker, bank or broker.other nominee. Many organizations allow beneficial owners to give voting instructions via telephone or the Internet, as well as in writing. You also are invited to attend the Annual Meeting, but you will need to bring a copy of a brokerage statement reflecting stock ownership as of March 6, 2015.19, 2018. Because you are not the stockholder of record, you may not vote your shares in person at the meeting unless you provide a valid proxy (sometimes referred to as a “legal proxy”) from your broker, bank or other similar organization.nominee.

How many votes do I have?

You have one vote for each share of Common Stock you own as of the close of business on March 6, 2015.19, 2018 for each matter to be voted on at the Annual Meeting. You may vote on each proposal presented for consideration at the 2015 Annual Meeting. There are no cumulative voting rights with respect to our Common Stock.

What if I return a proxy card but do not make specific choices?

If you return a signed and dated proxy card without marking any voting selections, your shares will be voted“For”the election of each of the seven (7)six (6) nominees for director, and“For”ratification of Baker Tilly Virchow Krause, LLPSchneider Downs & Co., Inc. as our independent registered public accounting firm for the year ending December 31, 2015.2018. If any other matter is properly presented at the meeting, your proxy (one of the individuals named on your proxy card) will vote your shares using his or her best judgment.

What do I need to do to attend the Annual Meeting in person?

Space for the Annual Meeting is limited. Therefore, admission will be on a first-come, first-served basis. Registration will open at 9:0045 a.m. Eastern Daylight Time, and the Annual Meeting will begin at 10:00 a.m. Each stockholder should be prepared to present:

Use of cameras, recording devices, computers and other electronic devices, such as smart phones and tablets, are not be permitted at the Annual Meeting. Photography and video are prohibited at the Annual Meeting.

Please allow ample time forcheck-in. Please note that large bags and packages are not allowed at the Annual Meeting. Persons may be subject to search.

Who is paying for this proxy solicitation?

ExOne will pay for the entire cost of soliciting proxies. In addition to ExOne mailing these proxy materials, ExOne’s directors and employees also may solicit proxies in person, by telephone, or by other means of communication. Directors and employees will not be paid any additional compensation for soliciting proxies. ExOne may reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one set of proxy materials?

If you receive more than one set of proxy materials (including multiple notices,Internet Notices or multiple copies of this Proxy Statement, orNotice of Annual Meeting and proxy cards)card), your shares are registered in more than one name or are registered in different accounts. Please make sure that you vote all of your shares by following the directions inon each noticeInternet Notice or completing, signing and returning each proxy card to ensure that all of your shares are voted.card.

Can I change my vote after submitting my proxy?

Yes. You can change your vote at any time before the final vote at the meeting.

If you are a stockholder of record, you may change your vote in any one of the following ways:

If you are a beneficial owner of shares held in street name, you may change your vote in any one of the following ways:

How are votes counted?

We have designated American Stock Transfer & Trust Company, LLPa representative of Broadridge Financial Services as the inspector of elections who will validate the votes.

With respect to Proposal No. 1, the inspector of elections will count“For” votes and“Against” votes. Abstentions and brokernon-votes will not be counted as having been voted on the proposal, nor will they affect the outcome of Proposal No. 1.

With respect to Proposal No. 2, the inspector of elections will count separately“For,” “Against” and“Abstain” votes and brokernon-votes.“Abstain”votes will be counted towards the vote total for the proposal, and will have the same effect as“Against”votes. Because brokernon-votes are not deemed to be votes entitled to be cast, they will not affect the outcome of Proposal No. 2.

See “How many votes are needed to approve each proposal?” for further details regarding the votes needed to approve each proposal.

What is a “brokernon-vote”?

If your shares are held by your broker, bank or other similar organization as your nominee (that is, in “street name”), you will need to follow the voting instructions provided by that organization on how to vote your shares. If you do not provide voting instructions, your shares may constitute “brokernon-votes.” Generally, brokernon-votes occur on a matter when a broker, bank or other organizationnominee is not permitted to vote on that matter, including the election of directors, without instructions from the beneficial owner and instructions are not given.

In tabulating the voting result for any particular proposal, shares that constitute brokernon-votes are not considered entitled to vote on that proposal. Thus, while brokernon-votes will be counted as present for the purpose of determining the presence of a quorum at the meeting, brokernon-votes willnot affect the outcome of any matter being voted on at the meeting.

How many votes are needed to approve each proposal?

Proposal No. 1. Directors will be elected by the vote of thea majority of the shares cast with respect to the director at the Annual Meeting. This means that the number of votes cast“For” a director’s election must exceed the number of votes cast“Against” that director’s election. Stockholders may not cumulate votes in the election of directors. Abstentions and brokernon-votes will not be counted as having been voted on the proposal, nor will they affect the outcome of this proposal.

Proposal No. 2. Ratification of the appointment of Baker Tilly Virchow Krause, LLPSchneider Downs & Co., Inc. as ExOne’s independent registered public accounting firm for the year ending December 31, 20152018 requires the affirmative vote of a majority of the shares represented at the Annual Meeting and entitled to vote on this matter. Abstentions will have the same effect as an“Against” vote. Broker Because brokernon-votes are not deemed to be votes entitled to be cast, they will not be counted as having been voted onaffect the outcome of this proposal.

What are the Board’s voting recommendations?

What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if a majority of all outstanding shares entitled to vote is represented by stockholders present at the meeting or represented by proxy. On the

record date, there were 14,516,13716,202,119 shares of Common Stock outstanding and entitled to vote. This means that 7,258,069at least 8,101,060 shares must be represented by stockholders present at the meeting or represented by proxy to have a quorum. Your shares will be counted towards the quorum if you submit a valid proxy or vote at the meeting.

How can I find out the results of the voting at the Annual Meeting?

Preliminary voting results will be announced at the Annual Meeting. Final voting results will be published in a Current Report onForm 8-K filed with the SEC within four business days following the Annual Meeting. In the event we are unable to obtain the final voting results within four business days, we will file the preliminary voting results in a Current Report onForm 8-K within four business days following the Annual Meeting, and will file an amended Current Report onForm 8-K with the final voting results within four business days after the final voting results are known.

How can stockholders submit a proposal under Rule 14a-8 for inclusion in our Proxy Statement for the 20162019 Annual Meeting of Stockholders?

Our 20162019 Annual Meeting of Stockholders will be held on May 11, 201615, 2019 at 10:00 a.m. To be included in our Proxy Statement for the 20162019 Annual Meeting of Stockholders, stockholder proposals must comply with the requirements ofRule 14a-8 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). To be eligible for inclusion, such proposals must be received by ExOne by December 4, 2015,6, 2018, which is at least 120 calendar days before the anniversary date of the release of ExOne’s Proxy Statement to stockholders in connection with the previous year’s annual meeting.

How can stockholders submit nominations of persons for election to the Board of Directors or proposals of business to be transacted by the stockholders for the 20162019 Annual Meeting of Stockholders?

A stockholder of record may submit nominations of persons for election to the Board of Directors or proposals of business to be transacted by the stockholders only if he or she complies with Article III, Section 13 of our Amended and Restated Bylaws, as amended (the “Bylaws”). This section provides that a stockholder must give advance notice to our Corporate Secretary of any business, including nominations of directors for our Board, that the stockholder wishes to raise at the 20162019 Annual Meeting of Stockholders at our principal executive offices (i) not earlier than 120 days prior to such meeting and (ii) at least 45 days prior to the anniversary date of the filing of ExOne’s proxy statementProxy Statement with the SEC in connection with the previous year’s annual meeting. Therefore, for the 20162019 Annual Meeting, such notice must be received by ExOne no sooner than January 12, 201615, 2019 and no later than February 10, 2016.19, 2019.

With respect to a stockholder’s nomination of a candidate for our Board, the stockholder notice to our Corporate Secretary must contain certain information as set forth in our Bylaws about both the nominee and the stockholder making the nomination. With respect to any other business that the stockholder proposes, the stockholder notice must contain a brief description of such business, the reasons for conducting such business at the meeting, any personal or other direct or indirect material interest in such business of such stockholder and the beneficial owner, if any, on whose behalf the proposal is made, and certain other information specified in our Bylaws.

If you wish to bring a stockholder proposal or nominate a candidate for director, you are advised to review our Bylaws, which contain additional requirements about advance notice of stockholder proposals and director nominations.

If a stockholder wishes only to recommend a candidate for consideration by the Nominating and Governance Committee as a potential nominee for director, see the procedures discussed in “Corporate Governance — Nominating and Governance Committee.”

What are the implications of being an “emerging growth company”?

As a company with less than $1.0 billion in revenue during our last fiscal year, weWe qualify as an “emerging growth company” as defined in the Jumpstart our Business Startups Act of 2012 (the “JOBS Act”)JOBS Act). An emerging growth company may take advantage of specified reduced reporting requirements and is relieved of certain other significant requirements that are otherwise generally applicable to public companies.

As an emerging growth company:

We may choose to take advantage of some, but not all, of these reduced burdens. We will continue to operate under these provisions for up to five yearsthrough December 31, 2018, or such earlier time that we are no longer an emerging growth company. We would cease to be an emerging growth company if we have more than $1.0$1.07 billion in annual revenues, qualify as a “large accelerated filer” under the Exchange Act, which requires us to have more than $700 million in market value of our common stockCommon Stock held bynon-affiliates, or issue more than $1.0 billion ofnon-convertible debt over a three-year period. We may choose to take advantage of some, but not all, of these reduced burdens.

PROPOSAL 1 — ELECTION OF DIRECTORS

General

This year, the Nominating and Governance Committee has elected sevenselected six (6) nominees for election to the Board of Directors, andfor consideration at the Annual Meeting; our Board has approved the nominees. All nominees are current members of the Board. Each nominee elected as a director at the Annual Meeting will continue to serve until the 20162019 Annual Meeting of Stockholders, until his or her successor has been elected or qualified, or until his or her earlier death, resignation or removal.

David Burns will be stepping down as a director when his term expires at this Annual Meeting. The Nominating and Governance Committee has nominated Mr. William F. Strome to fill the vacancy created by the expiration of Mr. Burns’ term.

Director Qualifications

Our Nominating and Governance Committee believes each member of our Board of Directors possesses the individual qualities necessary to serve on ExOne’s Board, of Directors, including high personal and professional ethical standards and integrity, honesty and good values. Our directors are highly educated and have diverse backgrounds and extensive track records of success in what we believe are highly relevant positions with large international companies, firms and major private and public institutions. TheyOur directors have each demonstrated an ability to exercise sound judgment and have exhibited a commitment of service to ExOne and to the Board, and each of our directors possesses strong communication skills. In addition, we believe that each director brings the skills, experience and perspective that, when taken as a whole, createscreate a Board that possesses the requirements necessary to oversee ExOne’s business. Each nominee’s particular experience, qualifications, attributes and skills that led the Board to conclude that such nominee should serve as a director for ExOne are set forth below under“Nominees”.

Vote Required

Directors will be elected by the vote of thea majority of the shares cast with respect to the director at the Annual Meeting. This means that the number of votes cast“For” a director’s election must exceed the total number of votes cast“Against” that director’s election. Abstentions and brokernon-votes will not be counted as having been voted on the proposal, nor will they affect the outcome of Proposal No. 1.

If a nominee is not elected, the director shall offer to tender his or her resignation to the Board of Directors.Board. The Nominating and Governance Committee of the Board of Directors will make a recommendation to the Board of Directors as to whether to accept or reject the resignation, or whether other action should be taken. The Board of Directors will act on the Nominating and Governance Committee’s recommendation and publicly disclose its decision and rationale within 90 days following the date of the certification of the election results. The director who tenders his or her resignation will not participate in the Board’s decision with respect to that resignation.

The proxy holders intend to vote all proxies received by them“For” the nominees listed below unless otherwise instructed. In the event that any nominee is unable or declines to serve as a director at the time of the Annual Meeting, the proxies will be voted for any nominee who may be designated by the current Board of Directors to fill the vacancy. As of the date of this Proxy Statement, the Board of Directors is not aware that any nominee is unable or will decline to serve as a director.

The Board of Directors Recommends a Vote “FOR” the Election of All Nominees.Each Director Nominee.

Nominees

The following is a description of each nominee (in alphabetical order) for election to the Board of Directors:Board:

Name		Age		Experience and Qualification
Lloyd A. Semple		7578		Mr. Semple began serving on our Board of Directors on February 5, 2013 and currently serves as our Lead Director. He has beenserved as a professor of law at the Detroit Mercy School of Law in Detroit, Michigan sincefrom 2004 and servedthrough his retirement in 2015 (serving as its dean from 2009 to 2013.2013). Prior to 2004, he practiced law at Dykema Gossett, a Detroit-based law firm, where he was Chairman and Chief Executive Officer from 1995 to 2002. He has served as outside counsel and director for several business enterprises. He was a director of Argon ST from 2004 to 2010. Mr. Semple brings to our Board extensive legal and corporate governance expertise and experience from his nearly forty-year career as an attorney in private practice, where he focused primarily on general corporate matters, mergers and acquisitions, and financial markets and services. His extensive service as counsel and director of several businesses has been extremely beneficial as he serves as the Lead Director of our Board.

EXECUTIVE OFFICERS OF EXONE

The following table and the discussion below provide information about our executive officers as of March 6, 2015, each of whom is elected annually.19, 2018.

S. Kent Rockwell — Mr. Rockwell’s biography is set forth in “Proposal Numberunder “Proposal 1 – — Election of Directors” sectionDirectors” above.

JoEllen Lyons DillonLoretta L. Benec — Ms. DillonBenec has served as our Executive Vice President, Chief Legal OfficerGeneral Counsel and Corporate Secretary since December 2014,October 2017. Beginning in November 2016, Ms. Benec has provided corporate and she previouslycommercial legal services as General Counsel to Cumberland Highstreet Partners, Inc., a manufacturing consulting business. Previously, Ms. Benec was Assistant General Counsel for RTI International Metals, Inc. (now Arconic Inc.), a NYSE-listed global supplier of advanced titanium products primarily to the commercial aerospace market, from July 2010 to August 2015, and also served as our Chief Legal Officerits Secretary from April 2013 to August 2015 and as its Director of Corporate Secretary beginningGovernance from July 2010 to April 2013. Prior to RTI, Ms. Benec enjoyed a more than twelve-year career in March 2013. From May 2012 through February 2013, she was a legal consultant on our initial public offering. She previously was a partner at two nationalthe law firms, Reed Smith LLP from 2002 until 2011 and Buchanan Ingersoll & Rooney PC from 1988 until 2002, where she became a partner after starting as an associate with the firm. Ms. Dillon has served on the Boarddepartment of Directors of Mylan Inc.H. J. Heinz Company (now The Kraft Heinz Company), a NYSE-listed global pharmaceutical company, since May 2014. She also serves onpackaged food company. Ms. Benec received a B.A. in History with High Honors, cum laude from Dartmouth College in 1992 and a J.D., cum laude, from the Mylan Board’s Compliance Committee. Ms. Dillon was the former Chair, and currently serves as the Audit Committee ChairUniversity of the Allegheny District chapterPittsburgh School of the National Multiple Sclerosis Society. She also is a Vice President of the Wine & Spirits Advisory Council to the Pennsylvania Liquor Control Board.Law in 1995.

Rainer Hoechsmann — Mr. Hoechsmann has served as Chief Development Officer since January 1, 2014, and also has served as General Manager of ExOne GmbH and ExOne Property GmbH, subsidiaries of ExOne, since 2003 and 2013, respectively. He is responsible for our operations in Europe.Mr. Hoechsmann is the inventor and co-inventor of certain AM technology covered by a number of our patents. In 2003, he co-founded Prometal RCT GmbH in Augsburg, which is the predecessor to ExOne GmbH. In 1999, he co-founded Generis GmbH, one of the first companies implementing 3D printing applications, in Augsburg, Germany. Mr. Hoechsmann has received a number of industry awards, including the OCE Printing Award from OCE Printers AG, the Technical University of Munich Award for 3D Printing and the McKinsey & Company Start-Up Award. He is a member of the Association of German Engineers.

Rick Lucas — Mr. Lucas has served as our Chief Technology Officer since June 2012. He served inPrior to joining ExOne, he held various positions from October 2001 to June 2012 at Touchstone Research Laboratory, a broad-based product development research facility that focuses on the development of next-generation materials and products, where he directed operations and research activities and served as Director of Operations from March 2010 to June 2012. From November 1989 to October 2001, Mr. Lucas managed product development for Lake Shore Cryotronics, a privately held developer of cryogenic temperature sensors and other instrumentation. He currently is serving on the Governance Board for the National Additive Manufacturing Innovation Institute (NAMII), an additive manufacturing center.

Hans J. SackJames L. McCarley— Mr. Sack began servingMcCarley has served as our Chief Executive Officer since August 2016. Mr. McCarley formerly served as Executive Vice President on March 16,— Operations of RTI International Metals, Inc., a NYSE-listed global supplier of advanced titanium products primarily to the commercial aerospace market, from May 2010 until July 2015, when Alcoa Inc. acquired RTI by merger. Mr. McCarley also served in the same position during the transition period after the merger, through September 2015. PriorDuring his time at RTI, Mr. McCarley was its highest ranking operating officer, overseeing daily operations, asset and cash management, talent recruitment/retention, customer care, and growth strategy deployment. Mr. McCarley had previously served as the Chief Executive Officer of General Vortex Energy, Inc., a private developer of engine and combustion technologies, from September 2009 to becomingMay 2010. From 1996 through 2009, Mr. McCarley held a variety of management positions within the forging segment of Precision Castparts Company, including Division President of the Company, he served on our Board of Directors (and chaired the Strategic Oversight Committee)Wyman Gordon Forging West from December 17, 20142008 to March 10, 2015. Mr. Sack was a Managing Director of HEADWATERS | SC, a private consulting firm, from 2013 to March 2015. In that position, Mr. Sack worked on client engagements on matters relating to business growth strategy development2009, and implementation, operational improvement initiatives, and

acquisition and consolidation strategies and related due diligence. Prior to joining Headwaters, from 2010 to 2012, Mr. Sack served asVice President and CEOGeneral Manager of Berg Steel Pipe Corp., the U.S. subsidiary of Europipe GmbH, a global leader in large diameter pipe for oil and gas pipelines. Mr. Sack served as President & CEO of Latrobe Specialty Steel Company, a producer of aerospace metals and tool steels owned by private equity firms,Wyman Gordon Forging, Inc. from 2006 to 2009.2008. From 19901987 to 2006,1996, he gained engineering and other relevant experience working for various companies, including Quantum Chemical, Cameron Iron Works, and General Electric Company. Mr. Sack worked for The Timken Company’s (NYSE: TKR) steel business, which is now known as TimkenSteel Corporation (NYSE: TMST), beginning in 1990 as a senior steel business specialist, serving in subsequent positions in the Steel Group as manager–small bar mill, project manager–parts strategy, general manager–precision steel components, and vice president–manufacturing–steel, becoming President & CEO of Timken Latrobe Steel in 1996 and becoming an officer of The Timken Company in 1998. Mr. SackMcCarley received a master’s degreeB.S. in mechanical engineeringElectrical Engineering from RWTH Aachen, Germany, and a master’s degreeTexas Tech University in business administration from the Harvard University Graduate School of Business Administration. Mr. Sack is a member of the Board of Directors of Saint Vincent College and its McKenna School of Business, Economics and Government.1987.

Brian W. Smith — Mr. Smith has served as our Chief Financial Officer and Treasurer since January 1, 2014. Mr. Smith previously was an Assurance Client Service Partner in the Pittsburgh office of PricewaterhouseCoopers LLP (“PwC”). Mr. Smith joined PwC in 1984, was admitted as a Partner in 1995, and has spent several years working in a PwC advisory business assisting industrial products, healthcare and energy companies with internal control reviews, system implementations, process transformation and change management. Mr. Smith held various leadership roles within PwC through December 2013, including leading initiatives in specific consumer and industrial product sectors. Mr. Smith ishas held leadership roles in a Certifiednumber charitable and professional organizations and currently sits on the Board of Trustees of The Pittsburgh Public AccountantTheater, The Ruffed Grouse Society and received a B.A. with a concentration in accounting and minor in economics from Westminster College in 1980.Chartiers Country Club.

CORPORATE GOVERNANCE

Highlights of Our Corporate Governance Practices

Our Board is committed to establishing and maintaining corporate governance policies and practices that are appropriate for a company like ExOne. Highlights of our implemented measures include:

Structure and Size of the Board of Directors

Our Board of Directors may establish the authorized number of directors from time to timetime-to-time by resolution, as permitted under our Bylaws. Currently, the Board of Directors has established that the Board will have sevensix (6) members. Our current directors, (ifif elected at the Annual Meeting)Meeting, will continue to serve until the 20162019 Annual Meeting of Stockholders, until his or her successor has been elected or qualified, or until his or her earlier death, resignation or removal.

Independence of the Board of Directors and Committees

A majority of our Board of Directorsdirectors are independent under the applicable rules of the NASDAQ Stock Market.NASDAQ. The Board determined in February 20152018 that Messrs. Kilmer, Sellier,Pashke, Semple and SempleStrome and Ms. Wachtel each qualify as independent directors in accordance with the published listing requirements of NASDAQ. The Board also determined that William F. Strome, a nominee for election to the Board of Directors, will also qualify as an independent director in accordance with the NASDAQ requirements if he is elected to the Board at the 2015 Annual Meeting. Finally, the Board determined that Mr. Sack was independent during his tenure on the Board from December 2014 to March 10, 2015.

As required by the NASDAQ rules, the Board of Directors has made a subjective determination as to each independent director that no relationships exist which, in the opinion of the Board, of Directors, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In making these determinations, the directors reviewed and discussed information provided by the directors and ExOne with regard to each director’s business and personal activities as they may relate to us and our management.

Upon the election of the directors at the 20152018 Annual Meeting, we will have fivefour (4) out of sevensix (6) independent directors on the Board, and each committee will have only have independent members.

Board Leadership Structure and Our Independent Lead Director

Our Bylaws give the Board the flexibility to determine whether the roles of Chief Executive Officer and Board Chairman should be held by the same person or by two separate individuals. Currently, S. Kent Rockwell serves as bothIn August 2016, our Board made the decision to split the roles of Chairman and Chief Executive Officer, and appointed S. Kent Rockwell to serve as Executive Chairman and James L. McCarley to serve as our Chief Executive Officer.

Mr. Rockwell’s role as Executive Chairman is to focus on the strategy of the Company and its business and leading the Board. As the founder of the Company and former Chief Executive Officer, the Board believes that Mr. Rockwell has been managing ExOne (or its predecessors) since 2008.

At this time,is uniquely positioned to continue to take the lead on strategic planning for the Company, management succession issues and leading the Board has determined that havingwhile transitioning away from handling the Company’s daily operations. As the leader of the Board, Mr. Rockwell servecontinues to set Board agendas and lead Board meetings. As part of this transition, the Board appointed Mr. McCarley as both the Chief Executive Officer, who oversees and leads the Chairman is in the best interest of our stockholders. We believe this structure makes the best use of Mr. Rockwell’s extensive knowledge of ExOne, our strategic initiativesCompany’s operations and our industry and also fosters real-time communication between management and the Board.business.

The Board also has elected Mr. Semple to serve as the Lead Director of our independent directors.directors, which is an important role for our Company because he provides leadership to the Board if circumstances arise in which Mr. Rockwell (who is also a significant stockholder) may be, or may be perceived to be, in conflict with the Company. As the Lead Director, Mr. Semple:Semple also:

Generally, eachEach meeting of the Board of Directors includes a meeting of the independent directors (led by our Lead Director), which takes place without any members of management or employees present.

Risk Oversight Management

Our management is responsible for theday-to-day management of the risks that we face including, without limitation, strategic, financial, operational, legal/compliance and reputational risks.

Our Board, of Directors as a whole, has responsibility for the oversight of enterprise risk management, and our Audit Committee is responsible for overseeing the process by which management assesses and manages our exposure to risk, as well as our major financial risk exposures and the steps management takes to monitor and control such exposures, based on consultation with our management and independent auditors. The Board’s and Audit Committee’s oversight roles are supported by management reporting processes that are designed to provide the Board and the Audit Committee insight into the identification, assessment and management of critical risks. The Board receives regular updates related to risks and risk management.

Information Regarding the Board of Directors and its Committees

Our Board of Directors has established fourthree committees: an Audit Committee, a Compensation Committee and a Nominating and Governance Committee and a Strategic Oversight Committee.

The following table provides membership information for each of the Board committees as of March 26, 2015:19, 2018:

Below is a description of each committee of the Board of Directors. CopiesBoard. A copy of the charters of the Audit, Compensation and Nominating and Governance committees arecharter for each committee is posted on our website athttp://www.exone.com under the Corporate Governance section and within the Investor Relations section.

During 2014,2017, the Board met eighttwelve (12) times. During that period, each director attended 75% or more of the total meetings of the Board and the committees on which he or she served.

Audit Committee

The Audit Committee of our Board of Directors assists the Board of Directors in overseeing:

During 2014,2017, the Audit Committee met sevenfive (5) times. The current members of the Audit Committee are Messrs. SellierPashke and KilmerStrome and Ms. Wachtel, each of whom is independent for Audit Committee purposes under the rules and regulations of the SEC and the listing standards of NASDAQ. Mr. SellierStrome currently chairs the Audit Committee.

The Board of Directors has determined that Mr. SellierStrome is an “audit committee financial expert” as defined in Item 407(d)(5)(ii) ofRegulation S-K and that he, therefore, also satisfies the “financial sophistication” requirement of the NASDAQ rules. The designation does not impose on Mr. SellierStrome any duties, obligations or liabilities that are greater than are generally imposed on him as a member of the Audit Committee and the Board of Directors.Board.

Most importantly, the Audit Committee is overseeing ExOne’s remediation of the material weaknesses ExOne has identified in its internal controls over financial reporting. In connection with our initial public offering (“IPO”), ExOne concluded that there are material weaknesses in the design and operating effectiveness of ExOne’s internal control over financial reporting. A material weakness is a control deficiency, or combination of deficiencies, in internal control over financial reporting such that there is a reasonable possibility that a material misstatement of annual or interim financial statements will not be prevented or detected on a timely basis.

ExOne’s material weaknesses in internal control over financial reporting are:

With the oversight of senior management and our Audit Committee, we have put into place a comprehensive plan to remediate the underlying causes of the identified material weaknesses. Our plan throughout 2014 and into 2015 is to continue to take additional steps and implement measures to remediate the underlying causes of the identified material weaknesses including:

These ongoing efforts, collectively, give ExOne the opportunity to remediate the material weaknesses in internal controls when ExOne reports its results for the 2015 fiscal year.

Compensation Committee

The Compensation Committee is charged with the following responsibilities, among others:

During 2014,2017, the Compensation Committee met six (6) times. The current members of our Compensation Committee are Messrs. KilmerSemple and SempleStrome and Ms. Wachtel, each of whom is independent for Compensation Committee purposes under the rules and regulations of the SEC and the listing standards of NASDAQ (including those that became effective in 2014).NASDAQ. Ms. Wachtel currently chairs the Compensation Committee. Each of the members also is a “non-employee“non-employee director” within the meaning ofRule 16b-3 of the Exchange Act and an “outside director,” as that term is defined under Section 162(m) of the Internal Revenue Code of 1986.Act.

OurNeither our Executive Chairman nor Chief Executive Officer will not participateparticipates in the determination of his own compensation or the compensation of directors. However, he will makeeach makes recommendations to the Compensation Committee regarding the amount and form of the compensation of the other executive officers and key employees, and he will participateeach participates in the Compensation Committee’s deliberations about the compensation of the other executive officers and key employees. No other executive officers or employees will participate in the determination of the amount or form of the compensation of executive officers or directors.

ExOne has not retained any compensation consultants. In March 2015,2017, the Compensation Committee identifieddid not engage an independent compensation consultant that the Committee may engage to advise it on various executive compensation matters from time to time as the Committee may request. At that time, the Committee determined that the identified consultant was independent.it.

The Compensation Committee shall have the authority to delegate any of its responsibilities, along with the authority to take action in relation to such responsibilities, to one or more subcommittees as the Compensation Committee may deem appropriate in its sole discretion. The Compensation Committee reviews its charter annually to ensure that it complies with NASDAQ listing requirements.

Compensation Committee Interlocks and Insider Participation

None of Ms. Wachtell,Wachtel, Mr. KilmerStrome, or Mr. Semple, the current members of our Compensation Committee, has been an officer or employee of ExOne. None of our executive officers havehas served as a member of a Compensation Committeecompensation committee or the Boardboard of Directorsdirectors of any other entity that has an executive officer serving as a member of our Board of Directors or our Compensation Committee.

Nominating and Governance Committee

The Nominating and Governance Committee of our Board of Directors is charged with the following responsibilities, among others:

During 2014,2017, the Nominating and Governance Committee met four (4) times. The current members of our Nominating and Governance Committee are Messrs. Semple, KilmerPashke and Sellier,Strome, each of whom is independent under the listing standards of NASDAQ. Mr. Semple currently chairs the Nominating and Governance Committee.

Strategic Oversight Committee

The Strategic Oversight Committee of our Board of Directors is charged with overseeing the strategic direction of the Company.

Director Nomination Process

The Nominating and Governance Committee believes that members of the Board of Directors should have certain minimum qualifications, including having the highest professional and personal ethics and values, broad experience at the policy-making level in business, government, education, technology or public interest, a commitment to enhancing stockholder value, and sufficient time to carry out their duties and to provide insight and practical wisdom based on experience. The Nominating and Governance Committee also considers such other guidelines and various relevant career experience, relevant skills, such as an understanding of the telecommunications and high-speed Internet provider industries, financial expertise, diversity and local and community ties. While we do not maintain a formal policy requiring the consideration of diversity in identifying nominees for director, diversity is, as noted above, one of the factors our Nominating and Governance Committee considers in conducting its assessment of director nominees. We view diversity expansively to include those attributes that we believe will contribute to a Board of Directors that, through a variety of backgrounds, viewpoints, professional experiences, skills, educational experiences and other such attributes, is best able to guide ExOne and its strategic direction. Candidates for director nominees are reviewed in the context of the currentmake-up of the Board of Directors.Board. The Nominating and Governance Committee will conduct any appropriate and necessary inquiries into the backgrounds and qualifications of possible candidates after considering the function and needs of the Board of Directors.Board. The Nominating and Governance Committee meets to discuss and consider such candidates’ qualifications and then selects a nominee for recommendation to the Board of Directors.Board.

The Nominating and Governance Committee will consider director candidates recommended by stockholders, although a formal policy has not been adopted with respect to consideration of such candidates because stockholder recommendations may be informally submitted and considered by the Nominating and Governance Committee under its charter. Director candidates recommended by stockholders will be evaluated by the Nominating and Governance Committee using the same criteria as candidates identified by the Board of Directors or the Nominating and Governance Committee for consideration. If a stockholder of ExOne wishes to recommend a director candidate for consideration by the Nominating and Governance Committee, the stockholder should refer to pages 5-6page 6 of this Proxy Statement for information regarding advance notice. The stockholder recommendation should be delivered to the Corporate Secretary of ExOne at our principal executive offices and should include:

Code of Ethics and Business Conduct

Our Board of Directors has adopted a code of ethics and business conduct. The code of ethics and business conduct applies to all of our employees, officers and directors. The full text of our code of ethics and business conduct is posted on our website athttp://www.exone.com under the Corporate Governance section within the Investor Relations section. We will disclose any future amendments to the code of ethics and business conduct that relate to our executive officers on our website, as well as any waivers of the code of ethics and business conduct that relate to the executive officers of ExOne.

Stockholder Communications with the Board of Directors

Stockholders may communicate with our Board, of Directors, either generally or with a particular director, by writing to the following address:

The Board of Directors

c/o Chief Legal OfficerGeneral Counsel and Corporate Secretary

The ExOne Company

127 Industry Boulevard

North Huntingdon, PA 15642

Each such communication should set forth (i) the name and address of such stockholder, as they appear on ExOne’s books, and if the stock is held by a nominee, the name and address of the beneficial owner of the stock, and (ii) the class and number of shares of ExOne’s stock that are owned of record by such record holder and beneficially by such beneficial owner.

The person receiving such stockholder communication shall, in consultation with appropriate members of the Board of Directors as necessary, generally screen out communications from stockholders to identify communications that are (i) solicitations for products and services, (ii) matters of a personal nature not relevant for stockholders, or (iii) matters that are of a type that render them improper or irrelevant to the functioning of the Board of Directors and ExOne.

Attendance at Annual Meeting of Stockholders by the Board of Directors

We do not have a formal policy regarding attendance by members of the Board of Directors at our Annual Meeting of Stockholders. All directors and director nominees attended the 20142017 Annual Meeting of Stockholders. Directors are encouraged, but not required, to attend the 20152018 Annual Meeting of Stockholders.

TRANSACTIONS WITH RELATED PERSONS

Approval of Related PartyPerson Transactions

On March 26, 2013, the Board of Directors ofUnder its written policy, The ExOne adopted ourCompany Policy and Procedures with Respect to Related Person Transactions. Under the written policy,Transactions, ExOne will enter into or ratify related person transactions involving more than $50,000 only when the Board, of Directors, acting through the Audit Committee, has determined that the transaction in question is in, or is not inconsistent with, the best interests of ExOne. Prior to entering into a related person transaction, the related person shallis required to provide notice to the Chief Legal OfficerExOne’s chief legal officer of the facts and circumstances of the transaction. Upon determining that the proposed transaction involves an amount greater than $50,000 and is a related person transaction, the proposed transaction shallwill be submitted to the Audit Committee for consideration. The Audit Committee shallwill consider all relevant facts and circumstances and approve only those related person transactions that are in the best interests of ExOne and its stockholders.

Related Person Transactions Between

Revolving Credit Facility with LBM Holdings, LLC

On March 12, 2018, the Company and its ExOne Americas LLC and Entities ControlledExOne GmbH subsidiaries, as guarantors (collectively, the “Loan Parties”), entered into a Credit Agreement and related ancillary agreements with LBM Holdings, LLC (“LBM”), a company controlled by Mr. Rockwell,

ExOne has purchased certain raw materials our Executive Chairman (a related person), relating to a $15,000,000 revolving credit facility (the “Credit Agreement”) to provide additional funding for working capital and components, website design servicesgeneral corporate purposes. The Credit Agreement provides for a term of three years (through March 12, 2021) and bears interest at a rate of one month LIBOR plus an applicable margin of 500 basis points (approximately 6.7% at inception). The Credit Agreement requires a commitment fee of 75 basis points, or 0.75%, on the corporate use of an airplane and leased office space from related entities under common control by our Chairman and Chief Executive Officer, Mr. Rockwell. The cost of these products and/or services was approximately $90,000 for the year ended December 31, 2014. Noneunused portion of the transactions met a threshold requiring review and approvalfacility, payable monthly in arrears. In addition, anup-front commitment fee of 125 basis points, or 1.25% (approximately $187,500), was required at closing. Borrowings under ExOne’s related party transactions policy described above.

During 2014, ExOne also received the benefitCredit Agreement are required to be in minimum increments of $1,000,000. The Company may terminate or reduce the credit commitment at any time during the term of the corporate useCredit Agreement without penalty. The Company may also make prepayments against the Credit Agreement at any time without penalty. Borrowings under the Credit Agreement have been collateralized by the accounts receivable, inventories and machinery and equipment of the Loan Parties. The total estimated value of collateral was in significant excess of the maximum capacity of the Credit Agreement at inception. Prior to entering into the credit facility with LBM, the Audit Committee approved the transaction pursuant to The ExOne Company Policy and Procedures with Respect to Related Person Transactions. There have been no borrowings under the Credit Agreement since its inception.

At the time of execution of the Credit Agreement, the $15,000,000 in available loan proceeds were deposited into an airplane fromescrow account with an unrelated, third party financial institution pursuant to a related entityseparate Escrow Agreement by and among the parties. Loan proceeds held in escrow will be available to us upon our submission to the escrow agent of a loan request. Such proceeds will not be available to LBM until paymentin-full of the obligations under common control by Mr. Rockwell for no consideration.

Also in 2014, the Company entered into a mutually beneficial arrangement withCredit Agreement and termination of the titanium powder and atomization company Puris, LLP (“Puris”), a related entity under common control by Mr. Rockwell. Pursuant to this arrangement, the Company provided Puris with a 3D printing machine, ancillary equipment, and installation trainingCredit Agreement. Payments of principal and other services valued at $1.0 million in the aggregate. In return, the Company received consideration in the form of assets and cash valued at $1.0 million in the aggregate.

Consulting Transaction with Mr. Sack

In December 2014, the Company entered into a consulting arrangement with Hans J. Sack who was subsequently appointedobligations will be made to the Board on December 17, 2014. Total considerationescrow agent, while interest payments will be made directly to LBM. Provided there exists no potential default or event of default, the Credit Agreement and Escrow Agreement prohibit any acceleration of repayment of any amount outstanding under the consulting arrangement was approximately $75,000,Credit Agreement and prohibit termination of which $25,000 was paid in 2014 (as reported under “2014 Director Compensation”) and $50,00 was paid in 2015. In connection with his appointment to the Board, approvalCredit Agreement or withdrawal from escrow of this arrangement was approved under ExOne’s related party transactions policy described above.any unused portion of the Credit Agreement.

DIRECTOR COMPENSATION

20142017 Director Compensation

Our Nominating and Corporate Governance Committee of the Board is responsible for reviewing and setting the compensation of our directors. The Nominating and Corporate Governance Committee approved, and ournon-employee directors received, the following compensation for 2014:2017:

The following table shows the compensation paid to ournon-employee directors in 2014.2017.

Directors who are also full-time officers or employeesMr. Rockwell, as an officer of ExOne (Messrs. Burns, Irvin and Rockwell) dothe Company, does not receive any additional compensation for serving as directors.a director.

Annual cash retainer of $40,000;

Significant Equity Ownership Creates Strong Alignment Between Our Leadership Team and Our Stockholders

We believe that the interests of the ExOneExOne’s executive teamofficers are strongly aligned with the interests of our stockholders. Four outstockholders through equity ownership. Our Executive Chairman, Mr. Rockwell, is ExOne’s largest beneficial owner (as the beneficial owner of five membersapproximately 28.4% of ExOne’sour outstanding Common Stock as of March 19, 2018). In addition, certain of our other executive teamofficers have significant ownership in the Company having invested their own money in ExOne before or in connection withand all of them have been granted equity incentive awards for their service to the IPO. Chairman and Chief Executive Officer Kent Rockwell is ExOne’s largest beneficial owner, controlling over 20% of ExOne common stock.Company. This ownership provides a strong foundation of alignment between ExOne stockholders and the ExOne management team.

20142017 Compensation Considerations

For 2014, the Compensation Committee considered three elements of compensation:

Chairman and Chief2017, our Named Executive Officer Kent Rockwell is paidOfficers received a base salary of $300,000 per year. Our other executive officers are paid comparable base salaries. The amountcombination of base salary and equity incentive awards with the exception of Mr. Rockwell who received only a salary. The Compensation Committee determined not to establish a short-term cash bonus or an annual incentive award plan for 2017.

Salary for each executive dependsof our Named Executive Officers (except Mr. Rockwell) is based on the scope of the executive’sindividual’s responsibility, his or her leadership skills, and values, and his or her performance and length of service.    Mr. Rockwell receives a salary of $50,000 per year for his services as Executive Chairman.

2014 Performance Resulted in No Discretionary Cash Bonus for 2014

In 2014, ExOne made important progress but fell short of its goals. The Company achieved $43.9 million in revenues driven by 45% growth in global non-machine revenue 2014. In addressing compensation decisions for 2014, the Compensation Committee weighed ExOne’s 2014 performance. ExOne Chairmanelected to award stock options to Messrs. Cianci and Chief Executive Officer received minimal compensation above his base salary. In December 2014,McCarley, and restricted stock to Mr. Smith and Ms. Dillon, as incentive awards for 2017 with the goal of further aligning the interests of our Presidentexecutives with those of our stockholders as well as to retain and Chief Operating Officer stepped down from that role to another position withinreward the Company. No executive received a discretionary cash bonusexecutives for 2014.creating long-term value for our stockholders.

2013 Equity Incentive Plan

On January 24, 2013, ourThe Board of Directors adopted our 2013 Equity Incentive Plan (the “Plan”).on January 24, 2013. The 2013 Equity Incentive Plan was approved by stockholders on August 19, 2013. The purpose of the 2013 Equity Incentive Plan is to provide incentives to attract, retain and motivate eligible persons whose present and potential contributions are important to the success of ExOne and its subsidiaries, by offering them an opportunity to participate in ExOne’s future performance through the grant of awards. The 2013 Equity Incentive Plan permits a variety of awards to be made at the discretion of the Compensation Committee including stock options, restricted stock, restricted stock units,

stock bonus awards, performance awards and stock appreciation rights. The 2013 Equity Incentive Plan will terminate January 24, 2023, unless it is terminated earlier by our Board. The 2013 Equity Incentive Plan is administered by the Compensation Committee.

2014Equity grants under the 2013 Equity Incentive Awards

ThePlan are generally made two business days after the date of approval by the Compensation Committee granted equity incentive awardsCommittee. No person is eligible to certainreceive more than 100,000 shares in any calendar year under the 2013 Equity Incentive Plan, except that ExOne executives in 2014. The grants weremay choose to issue a new employee up to 500,000 shares under the plan in the formcalendar year in which the employee commences employment. The total grant pool is determined with reference to industry practice and impact on the Company’s capitalization. Total awards under the 2013 Equity Incentive Plan are limited by share count of eitherno more than 1,992,241 shares, which is 15% of the Company’s total outstanding shares immediately following its initial public offering. Individual awards are determined on a discretionary basis, principally with reference to an executive’s responsibility, salary structure and performance. Restricted stock options or restricted stock. Each award vests in equal parts over a three-year period.

We believe that equity awards reward individual performanceawarded under the 2013 Equity Incentive Plan is granted at fair market value and also maintain long-term stockholder focus. We also believe that equity awards serve as a retention tool for key membersthe exercise price of our management team. In determining grant amounts,each stock option awarded under the Compensation Committee considers each executive’s position with2013 Equity Incentive Plan is the Company, the executive’s responsibilities with the Company, the executive’s base salary and any other compensation awarded in that year. Stock options have value only to the extent that theclosing price of ExOne stock rises between the grant date and the exercise date. Restricted stock rewards and retains the executives by offering them the opportunity to retain the ExOne stock if they are still employed by us on the date of grant. Equity grants are subject to vesting requirements as determined by the restrictions lapse.Committee.

20152018 Annual Incentive PlanProgram

In March 2015,On February 7, 2018, the Compensation Committee adopted the 2015 ExOne Umbrella Annual Incentive Plan2018 senior executive annual incentive program (the “Program”), which is part of a comprehensive annual incentive compensation program that will be implemented throughout the Company.

The Program provides an opportunity for employees. The plan has been structured as a subplanperformance-based compensation to senior executive officers of the ExOne 2013 Equity Incentive Plan.

Company (excluding the Executive Chairman) (each an “Executive”), among others. The plan is an umbrella plan that provides a bonus opportunity to ExOne employees selected by the Compensation Committee, which include the Chairman and Chief Executive Officer. The bonus opportunitytarget annual incentive award for each employeeExecutive is expressed as a percentage of base salary. Paymentsalary – 50% for the Chief Executive Officer and 35% for the other Executives. Achievement of the bonusaward will be conditioned on the Company meeting targeted revenue and gross margincertain goals for 2015. Payment against each financial performance measure2018 relating to revenue growth, adjusted EBITDA (earnings before interest, taxes, depreciation and amortization) (as described below), total cash and restricted cash (net of any debt incurred) and stockholder value (collectively, the “Goals”). Adjusted EBITDA is defined as net income (loss), as calculated under accounting principles generally accepted in the United States, plus interest expense, provision (benefit) for income taxes, depreciation and amortization, equity-based compensation, and other (income) expense – net. Added to adjusted EBITDA will only commence if the minimum threshold of 95%also be certain qualifying research and development expenses, Program expenses and other costs.

An Executive will earn payment of the performanceaward based on achievement of the equally-weighted Goals, as then adjusted by a multiplier that could decrease or increase the award depending on the number of goals achieved. In no event may payment exceed 125% of the target is achieved. Thereafter, paymentsannual incentive award for each Executive. The Compensation Committee retains negative discretion over final payment amounts.

Final payment will be tiedmade to the percentage level of performance achieved, with a maximum bonus of 125% of salary that can be earned.

After calculation of the formulaic payoutExecutives 100% in common stock based on the Company’s actual performance for 2015,closing stock price of the plan permitsCompany on the Compensation Committee to exercise negative discretion to reduce an executive’s bonus based on an annual individual performance review. In addition, the measurementdate of specific individual performance goals developed for an executive may also be used to reduce the payout. In addition, the Compensation Committee at all times has the discretion to reduce or eliminate all payment or awards under the plan for any reason without regard to any particular factors. Payment of earned awards will be 50% in cash2013 Equity Incentive Plan. The performance period begins January 1, 2018 and 50% in stock options and/or restricted stock unless the Compensation Committee elects a different form or mix of payment. In addition,ends on December 31, 2018, and continued employment through the payment date of payment is required.

This plan is structured to comply with the requirements of Section 162(m) of the Internal Revenue Code.

No Perquisites

The Company does not provide any perquisites to its Chief Executive Officer or other executive officers other than a Company contribution to a 401(k) retirement plan sponsored by the Company.

Benefits

We provide our named executives with other benefits that we believe are reasonable, competitive and consistent with our overall executive compensation program.

Clawback Policy and Other Actions Available to ExOne for Misconduct

In March 2015, theThe Compensation Committee has adopted a clawback policy that enables ExOne to recover all or any portion of any “Performance-Based Compensation” granted or paid to any current or former “Section 16 Officer”, or in which any current or former Section 16 Officer became vested, at any time within the three (3) year period immediately preceding the date on which ExOne is required to prepare an accounting restatement due to material noncompliancenon-compliance with any financial reporting requirements under the securities laws, as determined by the Audit Committee and confirmed by our independent registered public accounting firm.

In addition, in cases of detrimental misconduct by an executive officer, the Board may also take a range of other actions to remedy the misconduct, prevent its recurrence, and discipline the individual as appropriate, including, depending on the facts and circumstances, terminating the individual’s employment. These remedies would be in addition to, and not in lieu of, any actions imposed by law enforcement agencies, regulators or other authorities.

Stock Retention Policy and Equity Grant Practices