As filed with the Securities and Exchange Commission on January 8,August 21, 2013

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

The ExOne Company

(Exact name of registrant as specified in its charter)

127 Industry Boulevard

North Huntingdon, Pennsylvania 15642

(724) 863-9663

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

S. Kent Rockwell

Chairman & CEO

The ExOne Company

127 Industry Boulevard

North Huntingdon, Pennsylvania 15642

(724) 863-9663

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale to the public: As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended (the “Securities Act”), check the following box.    ¨

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

The Registrant is an “emerging growth company,” as defined in Section 2(a) of the Securities Act. This registration statement complies with the requirements that apply to an issuer that is an emerging growth company.

CALCULATION OF REGISTRATION FEE

The Registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this preliminary prospectus is not complete and may be changed. We and the selling stockholder may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and we and the selling stockholder areit is not soliciting an offer to buy these securities in any statejurisdiction where the offer or sale is not permitted.

2,656,000 Shares

The ExOne Company

Common Stock

We are offering 1,106,000 shares of our common stock, and the selling stockholder isstockholders are offering an additional1,550,000 shares of our common stock. We will not receive any proceeds from the sale of shares by theour selling stockholder.stockholders.

This is our initial public offering, and prior to this offering, there has been no public market for our common stock. We anticipate that the initial public offering price of ourOur common stock will be between $         and $         per share. We will apply to list our common stockis listed on the NasdaqThe NASDAQ Global Market under the symbol “XONE.” As of August 20, 2013, the last reported sale price of our common stock on The NASDAQ Global Market was $69.29 per share.

Investing in our common stock involves a high degree of risk. Please read “Risk Factors” beginning on page 14 of this prospectus to read about the risks you should consider before investing.

We are an “emerging growth company” under the federal securities laws and will be subject to reduced public company reporting requirements. Investing in our common stock involves a high degreeSee “Prospectus Summary — Implications of risk. Please read “Risk FactorsBeing an Emerging Growth Company.” beginning on page 12 of this prospectus to read about the risks you should consider before investing.

We and

Some of the selling stockholderstockholders have granted the underwriters an option, exercisable within 30 days of the date of this prospectus, to purchase a maximum of 398,400 additional shares of our common stock, from us and the selling stockholder at the initial public offering price, less the underwriting discount, to cover over-allotments of shares, if any.

The If the underwriters exercise their over-allotment option in full, then the proceeds before expenses will reserve upbe $             to shares from this offering for sale, directly or indirectly, to certain of our employees, directors and officers, and certain other investors related to us, at the public offering price without payment of an underwriting discount or commission.selling stockholders.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The underwriters expect to deliver the shares of our common stock to purchasers against payment on or about                     , 2013.

FBR

The date of this prospectus is                     , 2013.

TABLE OF CONTENTS

We have not, and the underwriters have not, authorized anyone to provide you with any information other than that contained in this prospectus or in any free writing prospectus we may authorize to be delivered or made available to you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus may only be used where it is legal to offer and sell shares of our common stock. The information in this prospectus may be accurate only as of the date of this prospectus, regardless of the time of delivery of this prospectus or any sale of shares of our common stock. Our business, financial condition, results of operations and prospects may have changed since that date. We will update this prospectus as required by law. We are not, and the underwriters are not, making an offer of these securities in any jurisdiction where the offer is not permitted.

For investors outside the United States: Neither we nor the underwriters have done anything that would permit this offering or possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the shares of common stock and the distribution of this prospectus outside the United States.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to the registration statement of which this prospectus is a part or to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

RISK FACTORS

An investment in our common stock involves risks. You should carefully consider each of the following risks and all of the information set forth in this prospectus before deciding to invest in our common stock. The risks and uncertainties described below are not the only ones we face. If any of the following risks and uncertainties develops into actual events, our business, financial condition, results of operations and cash flows could be materially adversely affected. In that case, the price of our common stock could decline and you may lose all or part of your investment.

Risks Related to Our Business and Industry

We may not be able to significantly increase the number of materials in which we can print products fast enough to meet our business plan.

Our business plan is heavily dependent upon our ability to steadily increase the number of qualified materials in which our machines can print products, sincebecause this will increase our addressable market, both as to customers and products for customers. However, qualifying new materials is a complicated engineering task, and there is no way to predict whether, or when, any given material will be qualified. If we cannot hire people with sufficient skilled peopletechnical skills to work on qualifying new materials for printing, or if we lack the resources necessary to create a steady flow of new materials, we will not be able to meet our business plan goals and a competitor may emerge that is better at qualifying new materials, either of which would have an adverse effect on our business results.

Our future success in qualifying new materials for printing may attract more competitors into our markets, some which may be much larger than we are.

If we succeed in qualifying a growing number of materials for use in our 3D printing machines, that will increase our addressable market. However, as we create a larger addressable market, our market may become more attractive to other 3D printing companies or large companies that are not 3D printing companies, but which may see an economic opportunity in the markets we have created. Because we are a supplier of 3D printed products to industrial companies, an increase in the number of competitors for our addressable market is likely to adversely affect our business and financial results.

We may not be able to adequately increase demand for our products.

Our business plan is built around a steady increase in the demand for our products. However, only a relatively small number of our potential customers know of the existence of AM and are familiar with its capabilities, and even fewer understand the potential benefits of using AM to manufacture products. If we do not develop effective strategies to raise awareness among potential customers of the benefits of AM and 3D printing, we may be unable to achieve our planned rate of growth, which could adversely affect our results of operations.

We may not be able to hire the number of skilled employees that we need to achieve our business plan.

For our business to grow in accordance with our business plan, we will need to hire and retain additional employees with the technical competence and engineering skills to operate our machines, improve our technology and processes and expand our technological capability to print using an increasing variety of materials. People with these skills are in short supply and may not be available in sufficient numbers to allow us to meet the goals of our business plan. If we cannot obtain the services of a sufficient number of technically skilled employees, we may not be able to achieve our planned rate of growth, which could adversely affect our results of operations.

Our revenues and operating results may fluctuate.

Our revenues and operating results may fluctuate from quarter-to-quarter and year-to-year and are likely to continue to vary due to a number of factors, many of which are not within our control. A significant portion of

our machine orders are typically received during the third or fourth quarter of the fiscal year as a result of the timing of capital expenditures of our customers. Our machines typically are shipped within the quarter or the next quarter after orders are received. Thus, revenues and operating results for any future period are not predictable with any significant degree of certainty. We also typically experience weaker demand for our machines in the first and second quarters. For these reasons, comparing our operating results on a period-to-period basis may not be meaningful. You should not rely on our past results as an indication of our future performance.

Fluctuations in our operating results and financial condition may occur due to a number of factors, including, but not limited to, those listed below and those identified throughout this “Risk Factors” section:

Due to the foregoing factors, you should not rely on quarter-to-quarter or year-to-year comparisons of our operating results as an indicator of future performance.

We may not be able to generate operating profits.

Since our inception, we have not generated operating profits. In the event that we are unable to execute on our business plan, we may be unable to generate profits in the future.

Our operating expenses (which include research and development and selling, general and administrative expenses) for the six months ended June 30, 2013, were approximately $9.6 million compared with operating expenses of approximately $6.8 million for the six months ended June 30, 2012. We expect our operating expenses for the year ending December 31, 2013 to be between approximately $18.0 million and $21.0 million. The increases in our research and development expenses are due primarily to continued investment in our 3D printing machine and micromachinery technology and increased costs associated with our materials qualification activities, including additional research and development headcount. The increases in our selling, general and administrative expenses are due primarily to increased expenses in professional service fees (including legal, audit and other consulting expenses) and increased personnel costs associated with an increased headcount (including salaries and related benefits) in making the transition from a private company to a publicly traded company.

We expect that our operating expenses will continue to increase in future periods as we pursue our growth strategies. Based on our current plans, we further expect our operating expenses for the year ending December 31, 2014 to exceed our 2013 operating expenses by 20% to 25%. Any future increases in our research and development expenses and selling, general and administrative expenses will directly affect our future results of operations and may have an effect on our financial condition.

We may not be able to introduce new machines and related industrial materials acceptable to the market or to improve the technology and industrial materials used in our current machines.

Our revenues are derived from the sale of machines for, and products manufactured using, AM. Our market is subject to innovation and technological change. A variety of technologies have the capacity to compete against one another in our market, which is, in part, driven by technological advances and end-user requirements and preferences, as well as the emergence of new standards and practices. Our ability to compete in the industrial AM market depends, in large part, on our success in enhancing and developing new machines, our success in enhancing our current machines, our success in enhancing and adding to our technology, and our success in developing and qualifying new industrial materials in which we can print. We believe that to remain competitive

we must continuously enhance and expand the functionality and features of our products and technologies. However, we may not be able to:

If the market does not develop as we expect, our revenues may stagnate or decline.

The marketplace for industrial manufacturing is dominated by conventional manufacturing methods that do not involve AM technology. If AM technology does not gain market acceptance as an alternative for industrial manufacturing, or if the marketplace adopts AM based on a technology other than our technology, we may not be able to increase or sustain the level of sales of our products and machines and our results of operations would be adversely affected as a result.

Loss of key management or sales or customer service personnel could adversely affect our results of operations.

Our future success depends to a significant extent on the skills, experience and efforts of our management and other key personnel. We must continue to develop and retain a core group of management individuals if we are to realize our goal of continued expansion and growth. While we have not previously experienced significant problems attracting and retaining members of our management team and other key personnel, there can be no assurance that we will be able to continue to retain these individuals, and the loss of any or all of these individuals could materially and adversely affect our business. We do not carry key-man insurance on any member of management.

Our international operations pose currency risks, which may adversely affect our operating results and net income.results.

Our operating results may be affected by volatility in currency exchange rates and our ability to effectively manage our currency transaction and translation risks. In general, we conduct our business, earn revenue and

incur costs in the local currency of the countries in which we operate. As a result, our international operations present risks from currency exchange rate fluctuations. The financial condition and results of operations of each of our foreign operating subsidiaries are reported in the relevant local currency and then translated to U.S. dollars at the applicable currency exchange rate for inclusion in our combined consolidated financial statements. We do not manage our foreign currency exposure in a manner that would eliminate the effects of changes in foreign exchange rates. Therefore, changes in exchange rates between these foreign currencies and the U.S. dollar will affect the recorded levels of our foreign assets and liabilities, as well as our revenues, cost of goods sold, and operating margins, and could result in exchange losses in any given reporting period.

In the future, we may not benefit from favorable exchange rate translation effects, and unfavorable exchange rate translation effects may harm our operating results. In addition to currency translation risks, we incur currency transaction risks whenever we enter into either a purchase or a sale transaction using a different

currency from the currency in which we receive revenues. In such cases we may suffer an exchange loss because we do not currently engage in currency swaps or other currency hedging strategies to address this risk.

Given the volatility of exchange rates, we can give no assurance that we will be able to effectively manage our currency transaction and/or translation risks or that any volatility in currency exchange rates will not have an adverse affecteffect on our results of operations.

One of our principal stockholders will be able to exert substantial influence.

Following the completion of this offering, S. Kent Rockwell, our Chairman and Chief Executive Officer, will beneficially own approximately %23.50% of our outstanding shares of common stock following this offering (        %(22.02% if the underwriters exercise their overallotmentthe over-allotment option in full) and may have effective control over the election of our Board of Directors and the direction of our affairs. As a result, he could exert considerable influence over the outcome of any corporate matter submitted to our stockholders for approval, including the election of directors and any transaction that might cause a change in control, such as a merger or acquisition. Any stockholders who are in favor of a matter that is opposed by Mr. Rockwell would have to obtain a significant number of votes to overrule the votes of Mr. Rockwell. See “Principal Stockholders.”

We may need to raise additional capital from time to time if we are going to meet our growth strategy and may be unable to do so on attractive terms.

Expanding our business to meet theour growth strategy may require additional investments of capital from time to time, and our existing sources of cash and any funds generated from operations may not provide us with sufficient capital. For various reasons, including any current noncompliance with existing or future lending arrangements, additional financing may not be available when needed, or may not be available on terms favorable to us. If we fail to obtain adequate capital on a timely basis or if capital cannot be obtained at reasonable costs, we will not be able to achieve our planned rate of growth, which will adversely affect our results of operations.

We are highly dependent upon sales to certain industries.

For 2012,our most recent fiscal year ended (December 31, 2012), revenues of machines and products have beenwere concentrated to companies in the aerospace (17%(20%), automotive (34%(24%), heavy equipment (21%(26%), and energy/oil/gas (7%(13%) industries and those industries’ respective suppliers. To the extent any of these industries experience a downturn, our results of operations may be adversely affected. Additionally, if any of these industries or their respective suppliers or other providers of manufacturing services develop new technologies or alternatives to manufacture the products that are currently manufactured using our machines, it may adversely affect our results of operations.

We are dependent on a single supplier of printheads.

We currently rely on a single source to supply the printheads used by our machines. While we believe that there are other suppliers of printheads upon which we could rely, we could experience delays and interruptions if our supply is interrupted that might temporarily impact the financial performance of our business.

All of the equipment at our Troy, Michigan and Houston, Texas PSCs is subject to a lien which secures certain loans.

All of the equipment at our Troy, Michigan and Houston, Texas PSCs is owned by our variable interest entities (“VIEs”) TMF and Lone Star, respectively, and leased to us. Each of these companies borrowed money from one or more lending institutions to fund the purchase of the equipment which is leased to us. Each of these loans is secured by a lien on the equipment leased to us. If any of those loans goes into default, the lender could repossess the equipment which is security for that loan, which would adversely affect our business at the affected PSC until the equipment could be replaced.

We may not be able to manage the expansion of our operations effectively in order to achieve our projected levels of growth.

We have expanded our operations significantly in recent periods, and our business plan calls for further expansion over the next several years. We anticipate that further development of our infrastructure and an increase in the number of our employees will be required to achieve our planned broadening of our product offerings and client base, improvements in our machines and materials used in our machines, and our planned international growth. In particular, we must increase our marketing and services staff to support new marketing and service activities and to meet the needs of both new and existing customers. Our future success will depend in part upon the ability of our management to manage our growth effectively. If our management is unsuccessful in meeting these challenges, we may not be able to achieve our anticipated level of growth which would adversely affect our results of operations.

We may not be able to consummate and effectively integrate future acquisitions, if any.

We may from time to time engage in strategic acquisitions and partnerships with third parties if we determine that they will provide future financial and operational benefits. Successful completion of any strategic transaction depends on a number of factors that are not entirely within our control, including our ability to negotiate acceptable terms, conclude satisfactory agreements and obtain all necessary regulatory approvals. In addition, our ability to effectively integrate any potential acquisition into our existing business and culture may not be successful, which could jeopardize future operational performance for the combined businesses. Although we are currently exploring a combination of acquisitions, strategic investments, and/or alliances, some of which we believe will promote advances in pre-print and post-print process, there is no guarantee that we will complete such transactions on favorable terms or at all. The exploration, negotiation, and consummation of acquisitions, strategic investments and/or alliances may involve significant expenditures by us, which may adversely affect our results of operations at the time such expenses are incurred. We may not be able to successfully negotiate and complete a specific acquisition, investment, or alliance. In addition, any acquisition, investment or alliance may not be accretive to ExOne for a period of time which may be significant following the completion of such acquisition, investment or alliance.

Our planned expansion of our international sales is subject to various risks, and failure to manage these risks could adversely affect our results of operations.

Our business is subject to certain risks associated with doing business globally. OurFor our three most recent fiscal years ended (December 31, 2012, 2011 and 2010), our sales outside of the AmericasUnited States were 70.7%72.8%, 70.0% and 70.0% of our total sales in 2010 and 2011, respectively, and were 63.0% for the nine months ended September 30, 2012.70.7%, respectively. One of our growth strategies is to pursue opportunities for our business in several areas of the world outside of the United States, any or all of which could be adversely affected by the risks set forth below. Our operations outside of the United States are subject to risks associated with the political, regulatory and economic conditions of the countries in which we operate, such as:

Any of these factors could materially adversely affect sales of our products to global customers or harm our reputation, which could adversely affect our results of operations.

Global economic, political and social conditions have adversely impacted our sales and may continue to do so.

The uncertain direction and relative strength of the global economy, difficulties in the financial services sector and credit markets, continuing geopolitical uncertainties and other macroeconomic factors all affect spending behavior of potential end-users of our products. The prospects for economic growth in the United States and other countries remain uncertain and may cause end-users to further delay or reduce technology purchases. In particular, a substantial portion of our sales are made to customers in countries in Europe, which is experiencing a significant economic crisis. If global economic conditions remain volatile for a prolonged period or if European economies experience further disruptions, our results of operations could be adversely affected. The global financial crisis affecting the banking system and financial markets has resulted in a tightening of credit markets,

lower levels of liquidity in many financial markets and extreme volatility in fixed income, credit, currency and equity markets. These conditions may make it more difficult for our end-users to obtain financing.

Due to our plan to increase our global business activities, we may be adversely affected by violations of the FCPA, similar anti-bribery laws in other jurisdictions in which we currently or may in the future operate, or various international trade and export laws.

Our business plan envisions that we will conduct increasing amounts of business outside of the United States, which will create various domestic and foreign regulatory challenges. The Foreign Corrupt Practices Act of 1977, as amended (the “FCPA”), and similar anti-bribery laws in other jurisdictions generally prohibit U.S.-based companies and their intermediaries from making improper payments to non-U.S. officials for the purpose of obtaining or retaining business. We have policies and controls in place designed to ensure internal and external compliance with these and other anti-bribery laws. To ensure compliance, our anti-bribery policy and training on a global basis provides our employees with procedures, guidelines and information about anti-bribery obligations and compliance. Further, we require our partners, subcontractors, agents and others who work for us or on our behalf to comply with anti-bribery laws. We also have procedures and controls in place designed to ensure internal and external compliance. However, such anti-bribery policy, training, internal controls, and procedures will not always protect us from reckless, criminal or unintentional acts committed by our employees, agents or other persons associated with us. If we are found to be in violation of the FCPA or other anti-bribery laws (either due to actsthe intentional or inadvertenceinadvertent acts of our employees, or due to the actsintentional or inadvertenceinadvertent acts of others), we could suffer criminal or civil penalties or other sanctions, which could have a material adverse effect on our business. In addition, actual or alleged violations could damage our reputation and adversely affect our results of operations.

We rely on our information technology systems to manage numerous aspects of our business and customer and supplier relationships, and a disruption of these systems could adversely affect our results of operations.

We depend on our information technology, or “IT,” systems to manage numerous aspects of our business and provide analytical information to management. Our IT systems allow us to efficiently purchase products from our suppliers, provide procurement and logistic services, ship products to our customers on a timely basis, maintain cost-effective operations and provide superior service to our customers. Our IT systems are an essential component of our business and growth strategies, and a disruption to our IT systems could significantly limit our ability to manage and operate our business efficiently. These systems are vulnerable to, among other things, damage and interruption from power loss, including as a result of natural disasters, computer system and network failures, loss of telecommunication services, operator negligence, loss of data, security breaches and computer viruses. Any such disruption could adversely affect our results of operations.

We could be subject to personal injury, property damage, product liability, warranty and other claims involving allegedly defective products that we supply.

The products we supply are sometimes used in potentially hazardous applications, such as the assembled parts of an aircraft or automobile, that could result in death, personal injury, property damage, loss of production, punitive damages, and consequential damages. While we have not experienced any such claims to date, actual or claimed defects in the products we supply could result in our being named as a defendant in lawsuits asserting potentially large claims. Any such lawsuit, regardless of merit, could result in material expense, diversion of management time and efforts, and damage to our reputation, and could cause us to fail to retain or attract customers, which could adversely affect our results of operations.

We may not have adequate insurance for potential liabilities.

In the ordinary course of business, we may be subject to various product and non-product related claims, lawsuits and administrative proceedings seeking damages or other remedies arising out of our commercial operations. We maintain insurance to cover our potential exposure for most claims and losses. However, our

insurance coverage is subject to various exclusions, self-retentions and deductibles, may be inadequate or unavailable to protect us fully, and may be cancelled or otherwise terminated by the insurer. Furthermore, we face the following additional risks under our insurance coverage:

Even a partially uninsured claim of significant size, if successful, could materially adversely affect our business, financial condition, results of operations and liquidity. However, even if we successfully defend ourselves against any such claim, we could be forced to spend a substantial amount of money in litigation expenses, our management could be required to spend valuable time in the defense against these claims and our reputation could suffer, any of which could adversely affect our results of operations.

If any of our manufacturing facilities or PSCs are disrupted, sales of our products may be disrupted, which could result in loss of revenues and an increase in unforeseen costs.

We manufacture our machines at our facilities in Augsburg, Germany and North Huntingdon, Pennsylvania. Our PSCs are located in North Huntingdon, Pennsylvania; Houston, Texas; Troy, Michigan; Auburn, Washington; Augsburg, Germany; and Kanagawa, Japan.

On August 1, 2013, we purchased land in Gersthofen, Germany, in the district of Augsburg to build a new facility. The facility will comprise approximately 150,700 square feet of production, warehouse, service and research and development space as well as approximately 27,600 square feet for offices. We intend to consolidate our five existing leased facilities in Augsburg, which currently occupy an aggregate of approximately 77,500 square feet, into the new facility, providing expansion capacity to support our global growth strategy. We have selected a turnkey provider of construction services that focuses on Central Europe, Great Britain, Austria and Switzerland, to design and construct the new facility. We estimate that we will complete construction of the new facility in the second half of 2014. We estimate that the acquisition and construction of the new facility will cost approximately $20.0 million, which includes approximately $3.9 million to purchase the land.

If the operations of these facilities are materially disrupted, we would be unable to fulfill customer orders for the period of the disruption, we would not be able to recognize revenue on orders, and we might need to modify our standard sales terms to secure the commitment of new customers during the period of the disruption and perhaps longer. Depending on the cause of the disruption, we could incur significant costs to remedy the disruption and resume product shipments. Such a disruption could have an adverse effect on our results of operations.

Under applicable employment laws, we may not be able to enforce covenants not to compete and therefore may be unable to prevent our competitors from benefiting from the expertise of some of our former employees.

We generally enter into non-competition agreements with our employees. These agreements prohibit our employees, if they cease working for us, from competing directly with us or working for our competitors or clients for a limited period. We may be unable to enforce these agreements under the laws of the jurisdictions in which our employees work, including Germany and Japan, and it may be difficult for us to restrict our competitors from benefitting from the expertise of our former employees or consultants developed while working for us. If we cannot demonstrate that our legally protectable interests will be harmed, we may be unable to prevent our competitors from benefiting from the expertise of our former employees or consultants and our ability to remain competitive may be diminished.

Risks Related to Our Intellectual Property

We may not be able to protect our trade secrets and intellectual property.

While some of our technology is licensed under patents belonging to others or is covered by process patents which are owned or applied for by us, much of our key technology is not protected by patents. Since we cannot legally prevent one or more other companies from developing similar or identical technology to our unpatented technology, it is likely that, over time, one or more other companies may be able to replicate our technology,

thereby reducing our technological advantages. If we do not protect our technology or are unable to develop new technology that can be protected by patents or as trade secrets, we may face increased competition from other companies, which may adversely affect our results of operations.

We enjoy license rights and exclusivity of certain patents and intellectual property and cannot adequately estimate the effects of their expiration upon the entrance or advancement of competitors into the AM industrial market.

We have exclusive license and non-exclusive license rights to certain patents that we utilize in the industrial market. Some of these patents willexpired in November 2012 and others are scheduled to expire as early as November 2012.over the next two years. We cannot adequately estimate the effect that the expiration of these patents will have upon the entrance or advancement of other AM manufacturers into the industrial market. See “Business — Intellectual Property.”

We may not be able to obtain patent protection or otherwise adequately protect or enforce our intellectual property rights, which could impair our competitive position.

Our success and future revenue growth will depend, in part, on our ability to protect our intellectual property. We rely primarily on patents, trademarks, and trade secrets, as well as non-disclosure agreements and other methods, to protect our proprietary technologies and processes globally. Despite our efforts to protect our proprietary technologies and processes, it is possible that competitors or other unauthorized third parties may obtain, copy, use, or disclose our technologies and processes. We cannot assure you that any of our existing or future patents or other intellectual property rights will not be challenged, invalidated, or circumvented or will otherwise provide us with meaningful protection. We may not be able to obtain foreign patents corresponding to our U.S. or foreign patent applications. Even if foreign patents are granted, effective enforcement in foreign countries may not be available. If our patents and other intellectual property protections do not adequately protect our technology, our competitors may be able to offer products similar to ours. We may not be able to detect the

unauthorized use of our proprietary technology and processes or take appropriate steps to prevent such use. Our competitors may also be able to develop similar technology independently or design around our patents. Any of the foregoing events would lead to increased competition and lower revenue or gross margins,profits, which would adversely affect our results of operations.

We may be subject to alleged infringement claims.

We may be subject to intellectual property infringement claims from individuals, vendors, and other companies who have acquired or developed patents in the field of AM for purposes of developing competing products or for the sole purpose of asserting claims against us. Any claims that our products or processes infringe the intellectual property rights of others, regardless of the merit or resolution of such claims, could cause us to incur significant costs in responding to, defending, and resolving such claims, and may prohibit or otherwise impair our ability to commercialize new or existing products. If we are unable to effectively defend our technologies and processes, our market share, sales and profitability could suffer, which could adversely affect our results of operations.

Certain of our employees and patents are subject to German law.

Many of our employees work in Germany and are subject to German employment law. Ideas, developments, discoveries and inventions made by such employees and consultants are subject to the provisions of the German Act on Employees’ Inventions (Gesetz über Arbeitnehmererfindungen), which regulates the ownership of, and compensation for, inventions made by employees. We face the risk that disputes can occur between us and our employees or ex-employees pertaining to alleged non-adherence to the provisions of this act that may be costly to defend and take up our management’s time and efforts whether we prevail or fail in such dispute. In addition, under the German Act on Employees’ Inventions, certain employees retained rights to patents they invented or co-invented prior to 2009. Although most of these employees have subsequently assigned their interest in these patents to us, there is a risk that the compensation we provided to them may be deemed to be insufficient in the future and we may be required under German law to increase the compensation due to such employee for the use of their patent. In those cases where employees have not assigned their interests to us, we may need to pay compensation for the use of those patents. If we are required to pay additional compensation or face other disputes under the German Act on Employees’ Inventions, our results of operations could be adversely affected.

Risks Related to this Offering, the Securities Markets, and Ownership of Our Common Stock

Prior to this offering, there has been no public market for our common stock, and we cannot assure you that a market for our common stock will develop or that the market price of shares of our common stock will not decline following the offering.

We cannot assure you that a trading market will develop for our common stock after this offering or, if one develops, that such trading market can be sustained. We intend to apply to have our common stock listed on the Nasdaq Global Market, but we cannot assure you that our application will be approved. In addition, we cannot predict the prices at which our common stock will trade. The initial public offering price for our common stock

will be determined through our negotiations with the underwriters based on numerous factors, including the information set forth in this prospectus, our prospects and the prospects of our industry, an assessment of our management, our prospects for future earnings, the general condition of the securities markets, the recent market prices of, and demand for, publicly traded common stock of generally comparable companies and other factors deemed relevant by the underwriters and us. Neither we nor the underwriters can assure you that the initial public offer price will bear any relationship to the market price at which our common stock may trade after our initial public offering. Shares of companies offered in an initial public offering often trade at a discount to the initial offering price due to underwriting discounts and commissions and related offering expenses.Offering

We have broad discretion as to the use of the net proceeds from this offering and may not use them effectively.

We cannot specify with certainty the particular uses to whichhow we will putuse the net proceeds that we receive from this offering. Our management will havehas broad discretion in the application of the net proceeds, and we may use these proceeds in ways with which you may disagree or for purposes other than those contemplated at the time of the offering. The failure by our management to apply these funds effectively could have a material adverse effect on our business, financial condition and results of operation. Pending their use, we may invest the net proceeds from this offering in a manner that does not produce income or that loses value.

The market price of our common stock may fluctuate significantly.

The market price and liquidity of the market for shares of our common stock that will prevail in the market after this offering may be higher or lower than the price you payfluctuate and may be significantly affected by numerous factors, some of which are beyond our control and may not be directly related to our operating performance. These factors include:

Investors in this offering will experience immediate dilution upon the closing of the offering.

If you purchase shares of our common stock in this offering, you will experience immediate dilution of $    per share because the price that you pay will be greater than the pro forma net asset value per share of the

common stock you acquire. This dilution is in large part due to the expenses incurred by us in connection with the consummation of this offering. You will experience additional dilution upon exercise of options to purchase common stock under any potential equity incentive plan or if we issue awards to our employees under any potential equity incentive plan, or if we otherwise issue additional shares of our common stock at a price below the initial public offering price. For more information, see “Dilution.”

If equity research analysts do not publish research or reports about our business, or if they issue unfavorable commentary or downgrade our shares, the price of our shares could decline.

The trading market for our shares will relyrelies in part on the research and reports that equity research analysts publish about us and our business. We do not have control over these analysts, and we do not have commitments from them to write research reports about us. The price of our shares could decline if one or more equity research analysts downgrades our shares, issues other unfavorable commentary, or ceases publishing reports about us or our business.

Future sales of our shares could reduce the market price of our shares.

The price of our shares could decline if there are substantial sales of our common stock, particularly by our directors, their affiliates or our executive officers, or when there is a large number of shares of our common stock available for sale. The perception in the public market that our stockholders might sell our shares could also depress the market price of our shares. Substantially all of our existingOur executive officers, directors and selling stockholders prior to this offering are subject to lock-up agreements with the underwriters that restrict their ability to transfer their shares for at least 18090 days after the date of this prospectus.offering. Consequently, upon expiration of the lock-up agreements, an additional    ofapproximately 4,347,327 shares held by our existing officers or directors after accounting for shares sold in this offering (3,948,927 if the over-allotment option is exercised in full) will be eligible for sale in the public market. The market price of our shares may drop significantly when the restrictions on resale by our existing stockholders lapse and these stockholders are able to sell their shares into the market. If this occurs or continues, it could impair our ability to raise additional capital through the sale of securities should we desire to do so.

We are incurring increased costs as a result of operating as a public company, and our management is required to devote substantial time to new compliance initiatives.

As a public company whose shares are listed on the NASDAQ Global Market, we incur significant accounting, legal and other expenses that we did not incur as a private company, and these expenses will increase even more after we are no longer an “emerging growth company” (as described below). We incur significant costs associated with our compliance with the public company reporting requirements of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”), requirements imposed by the Sarbanes-Oxley Act (most notably Section 404), Dodd Frank Wall Street Reform and Protection Act, and other rules adopted, and to be adopted, by the SEC and the NASDAQ Global Market. Compliance with these rules and regulations have increased our legal and financial compliance costs, introduced new costs (including stock exchange listing fees and costs related to investor relations and stockholder reporting), and made certain activities more time-consuming and costly. These increased costs of doing business have increased our consolidated net loss. They also make it more difficult for us to obtain director and officer liability insurance, and we may incur substantial costs to maintain sufficient coverage.

In addition, changing laws, regulations and standards relating to corporate governance and public disclosure are creating uncertainty for public companies generally, increasing legal and financial compliance costs and making some activities more time consuming. These laws, regulations and standards are subject to varying interpretations, in many cases due to their lack of specificity, and, as a result, their application in practice may evolve over time as new guidance is provided by regulatory and governing bodies. This could result in continuing uncertainty regarding compliance matters and higher costs necessitated by ongoing revisions to disclosure and governance practices. We intend to invest resources to comply with evolving laws, regulations and standards, and this investment may result in increased general and administrative expenses and a diversion of management’s time and attention from revenue-generating activities to compliance activities. If our efforts to comply with new laws, regulations and standards differ from the activities intended by regulatory or governing bodies due to ambiguities related to their application and practice, regulatory authorities may initiate legal proceedings against us and our business may be adversely affected. We cannot predict or estimate the amount or timing of additional costs we may incur in the future to respond to these constantly evolving requirements. The impact of these requirements could also make it more difficult for us to attract and retain qualified persons to serve on our Board of Directors, our board committees or as executive officers.

However, for as long as we remain an “emerging growth company” as defined in the JOBS Act, we may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not “emerging growth companies” including, but not limited to, not being required to comply with the auditor attestation requirements of Section 404(b) of the Sarbanes-Oxley Act, less extensive disclosure obligations regarding executive compensation in our periodic reports and proxy statements, exemptions from the requirements to hold a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved and an extended transition period for complying with new or revised accounting standards. We may take advantage of these provisions for up to five years 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 billion in annual revenues, qualify as a “large accelerated filer” under the Securities Exchange Act of 1934, as amended (which requires us to have more than $700 million in market value of our common stock held by non-affiliates), or issue more than $1.0 billion of non-convertible debt over a three-year period. See “Shares Eligible“Prospectus Summary — Implications of Being an Emerging Growth Company.”

We have never paid cash dividends on our common stock, and we do not anticipate paying any cash dividends in the foreseeable future. Therefore, if our share price does not appreciate, our investors may not gain and could potentially lose on their investment in our shares.

We have never declared or paid cash dividends on our common stock, nor do we anticipate paying any cash dividends on our share capital, after this offering and in the foreseeable future. We currently intend to retain all available funds and any future earnings to fund the development and growth of our business. As a result, capital appreciation, if any, of our shares will be investors’ sole source of gain for Future Sale.the foreseeable future.

As an emerging growth company, we intend to follow certain permitted corporate governance practices instead of the otherwise applicable SEC and NASDAQ requirements, which may result in less protection than is accorded to investors in a non-emerging growth company.

As an emerging growth company, we will be permitted, and intend to follow, certain corporate governance practices instead of those otherwise required by the SEC and under the listing requirements of the NASDAQ Global Market. Following our emerging growth company governance practices as opposed to the requirements that would otherwise apply to a company listed on the NASDAQ Global Market may provide less protection to you than what is accorded to investors under the Listing Rules of the NASDAQ Stock Market applicable to non-emerging growth company issuers.

As an emerging growth company, we will delay adoption of new or revised accounting standards, which may make our stock less attractive and our trading price more volatile.

Pursuant to the JOBS Act, as an emerging growth company, we have elected to take advantage of an extended transition period for any new or revised accounting standards that may be issued by the Financial Accounting Standards Board (FASB) or the SEC, which means that when a standard is issued or revised and it has different application dates for public or private companies, we, as an emerging growth company, will delay adoption of the standard until it applies to private companies. This may make a comparison of our financial statements with any other public company that is either not an emerging growth company or is an emerging growth company that has opted out of using the extended transition period difficult, as different or revised standards may be used. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile and could decline.

If we fail to maintain an effective system of internal control over financial reporting in the future, we may not be able to accurately report our financial condition, results of operations or cash flows, which may adversely affect investor confidence in us and, as a result, the value of our common stock.

The Sarbanes-Oxley Act requires, among other things, that we maintain effective internal controls for financial reporting and disclosure controls and procedures. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure. In addition, commencing with our annual report on Form 10-K for the year ending December 31, 2013, we will be required, under Section 404(a) of the Sarbanes-Oxley Act, to furnish a report by management on, among other things, the effectiveness of our internal control over financial reporting. This assessment will need to include disclosure of any material weaknesses identified by our management in our internal control over financial reporting. A material weakness is a control deficiency, or combination of control deficiencies, in internal control over financial reporting that results in more than a reasonable possibility that a material misstatement of annual or interim financial statements will not be prevented or detected on a timely basis.

In connection with the preparation of our consolidated financial statements for the year ended December 31, 2012, we concluded that there are material weaknesses in the design and operating effectiveness of our internal control over financial reporting as defined in SEC Regulation S-X. A description of the identified material weaknesses in internal control over financial reporting are as follows:

The design and operating effectiveness of internal controls related to our financial reporting process were not sufficient to allow for accurate and timely reporting of our consolidated financial results.We did not maintain adequate control with respect to the application of GAAP. This was principally due to a lack of personnel with adequate knowledge and experience in GAAP. As a result, we recorded certain manual, post-close adjustments in order to prepare the consolidated financial statements included in this prospectus.

The design and operating effectiveness of internal controls related to our information technology systems was not sufficient to allow for accurate and timely reporting of our consolidated financial results.Each of our primary locations (United States, Germany and Japan) utilizes separate and distinct information technology platforms to record, process and summarize transactions. As a result, our process to consolidate and report financial information is substantially a manual process and inherently subject to error.

The design and operating effectiveness of internal controls related to our consolidation process and management’s review of our consolidated financial results did not operate at a level of precision sufficient to allow for accurate and timely reporting of our consolidated financial results.Our consolidation process is substantially a manual process and inherently subject to error. Further, because of internal control weaknesses identified with respect to our financial reporting process and information technology systems, management was unable to complete an adequate review of either subsidiary or consolidated financial results at a sufficient level of precision to prevent or detect misstatements. As a result, we recorded certain manual, post-close adjustments in order to prepare the consolidated financial statements included in this prospectus.

With the oversight of senior management and our audit committee, we have begun taking steps and plan to take additional measures to remediate the underlying causes of the identified material weaknesses. Our plan includes (i) enhancing our global accounting and reporting process by designing and strengthening the operating effectiveness of internal controls over financial reporting, (ii) evaluating our information technology systems to further integrate existing systems or invest in improvements to our technology sufficient to generate accurate and timely financial information, and (iii) adding financial personnel with adequate knowledge and experience in GAAP.

In addition to these efforts, we are in the process of documenting and testing our internal control over financial reporting in order to report on the effectiveness of our internal controls as of December 31, 2013. We can provide no assurance at this time that management will be able to report that our internal control over financial reporting is effective as of December 31, 2013. Furthermore, as our business continues to grow internationally, our internal controls will become more complex and will require significantly more resources and attention to ensure that our internal controls remain effective overall. If our management cannot favorably assess the effectiveness of our internal controls over financial reporting, investor confidence in our financial results may weaken, and our share price may suffer.

Notwithstanding the identified material weaknesses, management believes the consolidated financial statements included in this prospectus fairly present in all material respects our financial condition, results of operations and cash flows as of and for the periods presented in accordance with GAAP.

Additionally, Section 404(b) of the Sarbanes-Oxley Act requires an attestation from our independent registered public accounting firm on the effectiveness of our internal control over financial reporting. As an emerging growth company, we will not be required to comply with Section 404(b), until we file our annual report for 2018 with the SEC, provided we maintain our status as an emerging growth company for the full five-year period.

Our compliance with Section 404(b) will require that we incur substantial accounting expense and expend significant management efforts. We currently do not have an internal audit group, and we will need to hire additional accounting and financial staff with appropriate public company experience and technical accounting knowledge, and compile the system and process documentation necessary to perform the evaluation needed to comply with Section 404(b). We may not be able to complete our evaluation, testing and any required remediation in a timely fashion. During the evaluation and testing process, if we identify one or more material weaknesses in our internal control over financial reporting, we will be unable to assert that our internal control over financial reporting is effective. We cannot assure you that there will not be material weaknesses or significant deficiencies in our internal control over financial reporting in the future. Any failure to maintain internal control over financial reporting could severely inhibit our ability to accurately report our financial condition, results of operations or cash flows. If we are unable to conclude that our internal control over financial reporting is effective, or if our independent registered public accounting firm determines we have a material weakness or significant deficiency in our internal control over financial reporting once that firm begins its Section 404(b) attestations, we could lose investor confidence in the accuracy and completeness of our financial reports, the market price of our common stock could decline, and we could be subject to sanctions or investigations by NASDAQ, the SEC or other regulatory authorities. Failure to remedy any material weakness in

our internal control over financial reporting, or to implement or maintain other effective control systems required of public companies, could also restrict our future access to the capital markets.

Provisions in our charter documents or Delaware law may inhibit a takeover, which could adversely affect the value of our common stock.

Our certificate of incorporation and bylaws contain, and Delaware corporate law contains, provisions that could delay or prevent a change of control or changes in our management. These provisions will apply even if some of our stockholders consider the offer to be beneficial or favorable. If a change of control or change in management is delayed or prevented, the market price of our common stock could decline.

Investors in this offering will experience immediate dilution upon the closing of the offering.

If you purchase shares of our common stock in this offering, you will experience immediate dilution of $per share because the price that you pay will be greater than the pro forma net asset value per share of the common stock you acquire. This dilution is also due to the expenses incurred by us in connection with the consummation of this offering. You will experience additional dilution upon the exercise of options to purchase our common stock or the vesting of other grants of equity awards made by us under the Plan, or any other equity incentive plan that we may adopt in the future, or if we otherwise issue additional shares of our common stock at a price below the offering price. See “Dilution.”

Raising additional capital by issuing securities may cause dilution to our stockholders.

We may need or desire to raise substantial additional capital in the future. Our future capital requirements will depend on many factors, including, among others:

If we raise additional funds by issuing equity or convertible debt securities, we will reduce the percentage ownership of our then-existing stockholders, and the holders of those newly-issued equity or convertible debt securities may have rights, preferences, or privileges senior to those possessed by our then-existing stockholders. Additionally, future sales of a substantial number of shares of our common stock or other equity-related securities in the public market could depress the market price of our common stock and impair our ability to raise capital through the sale of additional equity or equity-linked securities. We cannot predict the effect that future sales of our common stock or other equity-related securities would have on the market price of our common stock.

We will incur increased costs as a result of operating as a public company, and our management will be required to devote substantial time to new compliance initiatives.

As a public company whose shares are listed on the Nasdaq Global Market, we will incur accounting, legal and other expenses that we did not incur as a private company. We will incur costs associated with our public company reporting requirements of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”). We also anticipate that we will incur costs associated with corporate governance requirements, including requirements under Section 404 and other provisions of the Sarbanes-Oxley Act, as well as rules implemented by the SEC, the listing requirements of the Nasdaq Global Market and the Nasdaq Marketing Rules and other applicable securities rules and regulations. Compliance with these rules and regulations will increase our legal and financial compliance costs, introduce new costs such as investor relations, stock exchange listing fees and stockholder reporting, and will make some activities more time-consuming and costly. We are currently evaluating and monitoring developments with respect to these rules, and we cannot predict or estimate the amount of additional costs we may incur or the timing of such costs.

In addition, changing laws, regulations and standards relating to corporate governance and public disclosure are creating uncertainty for public companies, increasing legal and financial compliance costs and making some activities more time consuming. These laws, regulations and standards are subject to varying interpretations, in many cases due to their lack of specificity, and, as a result, their application in practice may evolve over time as new guidance is provided by regulatory and governing bodies. This could result in continuing uncertainty regarding compliance matters and higher costs necessitated by ongoing revisions to disclosure and governance practices. We intend to invest resources to comply with evolving laws, regulations and standards, and this investment may result in increased general and administrative expenses and a diversion of management’s time and attention from revenue-generating activities to compliance activities. If our efforts to comply with new laws, regulations and standards differ from the activities intended by regulatory or governing bodies due to ambiguities related to their application and practice, regulatory authorities may initiate legal proceedings against us and our business may be adversely affected.

However, for as long as we remain an “emerging growth company” as defined in the JOBS Act, we may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not “emerging growth companies” including, but not limited to, not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act, or Section 404, less extensive disclosure obligations regarding executive compensation in our periodic reports and proxy statements, exemptions from the requirements to hold a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved and an extended transition period for complying with new or revised accounting standards. We may take advantage of these reporting exemptions until we are no longer an “emerging growth company.” We may remain an “emerging growth company” for up to five years. See “Summary — Implications of Being an Emerging Growth Company.”

We have never paid cash dividends on our equity interests, and we do not anticipate paying any cash dividends in the foreseeable future. Therefore, if our share price does not appreciate, our investors may not gain and could potentially lose on their investment in our shares.

We have never declared or paid cash dividends on our common interests, nor do we anticipate paying any cash dividends on our share capital, after this offering and in the foreseeable future. We currently intend to retain all available funds and any future earnings to fund the development and growth of our business. As a result, capital appreciation, if any, of our shares will be investors’ sole source of gain for the foreseeable future.

As an emerging growth company, we intend to follow certain permitted corporate governance practices instead of the otherwise applicable SEC and Nasdaq requirements, which may result in less protection than is accorded to investors in a non-emerging growth company.

As an emerging growth company, we will be permitted, and intend to follow, certain permitted corporate governance practices instead of those otherwise required by the SEC and under the listing requirements of the

Nasdaq Global Market. Following our emerging growth company governance practices as opposed to the requirements that would otherwise apply to a company listed on the Nasdaq Global Market may provide less protection to you than what is accorded to investors under the Listing Rules of the Nasdaq Stock Market applicable to non-emerging growth company issuers.

As an emerging growth company, we may delay adoption of new or revised accounting standards, which may make our stock less attractive and our trading price more volatile.

Pursuant to the JOBS Act, as an emerging growth company, we have elected to take advantage of an extended transition period for any new or revised accounting standards that may be issued by the Financial Accounting Standards Board (FASB) or the SEC, which means that when a standard is issued or revised and it has different application dates for public or private companies, we, as an emerging growth company, can delay adoption of the standard until it applies to private companies. This may make a comparison of our financial statements with any other public company that is either not an emerging growth company or is an emerging growth company that has opted out of using the extended transition period difficult, as different or revised standards may be used. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile and could decline. Some of the exceptions from disclosure provided for emerging growth companies are also available to smaller reporting companies. We will continue to make use of these overlapping exemptions so long as we are an emerging growth company, even if at some point in the future we are no longer a smaller reporting company.

If, after this offering, we are unable to satisfy the requirements of Section 404 of the Sarbanes-Oxley Act as they apply to an emerging growth company that is listed on an exchange for the first time, or if our internal controls over financial reporting are not effective, the reliability of our financial statements may be questioned and our share price may suffer.

After the completion of this offering, we will become subject to the requirements of Section 404(a) of the Sarbanes-Oxley Act, which requires a company that is subject to the reporting requirements of the U.S. securities laws to conduct a comprehensive evaluation of its and its subsidiaries’ internal controls over financial reporting. To comply with this statute, we will be required to document and test our internal control procedures, and our management will be required to assess and issue a report concerning our internal controls over financial reporting.

We will need to prepare for compliance with Section 404 by strengthening, assessing and testing our system of internal controls to provide the basis for our management’s report. However, the continuous process of strengthening our internal controls and complying with Section 404(a) is complicated and time-consuming. Furthermore, as our business continues to grow internationally, our internal controls will become more complex and will require significantly more resources and attention to ensure that our internal controls remain effective overall. We have been made aware of a material weakness in our internal controls over financial reporting by our independent registered public accounting firm. We have taken steps to remediate this material weakness and plan to take further steps in the future. Section 404 requires annual management assessments of the effectiveness of our internal controls over financial reporting. Assuming that we continue to qualify as an emerging growth company for the next five years, we will be required to comply with Section 404(b) at the time we file our annual report for 2018 with the SEC. Over the course of testing our internal controls, our management may identify material weaknesses or significant deficiencies, which may not be remedied in a timely manner to meet the deadline imposed by the Sarbanes-Oxley Act. If our management cannot favorably assess the effectiveness of our internal controls over financial reporting, investor confidence in our financial results may weaken, and our share price may suffer.

Provisions in our charter documents or Delaware law may inhibit a takeover, which could adversely affect the value of our common stock.

Our certificate of incorporation and bylaws will contain, and Delaware corporate law contains, provisions that could delay or prevent a change of control or changes in our management. These provisions will apply even if some of our stockholders consider the offer to be beneficial or favorable. If a change of control or change in management is delayed or prevented, the market price of our common stock could decline. See “Description of Capital Stock.”

CAUTIONARY STATEMENT CONCERNING FORWARD LOOKING STATEMENTS

We are including the following discussion to inform you of some of the risks and uncertainties that can affect us.

This prospectus contains various forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and, Section 21E of the Exchange Act, including those that express a belief, expectation, or intention, as well as those that are not statements of historical fact, that are forward looking statements. The forward looking statements may include projections and estimates concerning the timing and success of specific projects and our future production, revenue, income and capital spending. Our forward looking statements are generally accompanied by words such as “may,” “will,” “expect,” “intend,” “estimate,” “project,” “predict,” “believe,” “expect,” “anticipate,” “potential,” “plan,” “goal” or other words that convey the uncertainty of future events or outcomes. The forward looking statements in this prospectus speak only as of the date of this prospectus; we disclaim any obligation to update these statements (unless required by securities laws), and we caution you not to unduly rely on them. We have based these forward looking statements on our current expectations and assumptions about future events. While our management considers these expectations and assumptions to be reasonable, they are inherently subject to significant business, economic, competitive, regulatory and other risks, contingencies and uncertainties, most of which are difficult to predict and many of which are beyond our control. These risks, contingencies and uncertainties include, but are not limited to, the following:

These and other important factors, including those discussed under “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included elsewhere in this prospectus, may cause our actual results of operations to differ materially from any future results of operations

expressed or implied by the forward looking statements contained in this prospectus. Before making a decision to purchase our common stock, you should carefully consider all of the factors identified in this prospectus that could cause actual results to differ from these forward looking statements.

You should rely only on the information contained or incorporated by reference in this prospectus and in any free writing prospectus that we have authorized for use in connection with this offering. Neither we nor the

underwriters nor the selling stockholderstockholders have authorized any other person to provide you with additional or different information. If anyone provides you with different or inconsistent information, you should not rely on it. Neither we nor the underwriters nor the selling stockholderstockholders are making an offer to sell these securities in any jurisdiction where an offer or sale is not permitted. You should assume that the information in this prospectus is accurate only as of the date on the front cover of this prospectus, regardless of the time of delivery of this prospectus or any sale of our common stock. Our business, financial condition, results of operations and prospects may have changed since that date.

Through and including             , 2013 (25 days after However, we will update this prospectus to reflect any material changes to the commencementinformation contained herein during the period of this offering), all dealers that effect transactions in these securities, whether or not participating in this offering, may be required to deliver a prospectus. This is in addition to the dealer’s obligation to deliver a prospectus when acting as an underwriter and with respect to unsold allotments or subscriptions.offering.

MARKET AND INDUSTRY DATA

This prospectus contains industry, market and competitive position data that are based on industry publications and studies conducted by third parties, including, but not limited to, the 2013 report of Wohlers Report,Associates, Inc., “Additive Manufacturing and 3D Printing State of the Industry” (the “2013 Wohlers Report”), in which we were an industry participant in 2012.2013. The industry publications and third-party studies generally state that the information that they contain has been obtained from sources believed to be reliable, although they do not guarantee the accuracy or completeness of such information. While we believe that each of these publications and third-party studies is reliable, we have not independently verified the market and industry data obtained from these third-party sources.

TRADEMARKS, SERVICE MARKS AND TRADE NAMES

This prospectus includes our trademarks, service marksWe have registrations in the United States for X1. We have filed for trademark registrations in the United States and trade names, such as “EXONE,in Canada, Europe, Japan, China, Korea, and Brazil for ExOne and for a stylized form of “X1 ExOne DIGITAL PART MATERIALIZATION.” our logo,We have also filed for trademark registrations in Canada and “ExOne,” which are protected under applicable intellectual property lawsJapan for DIGITAL PART MATERIALIZATION. We have also filed for trademark registrations in the United States for ExCAST, ExMAL, ExTEC, and are the property of The ExOne Company and our subsidiaries.M-Flex. This prospectus also contains trademarks, service marks and trade names of other companies, which are the property of their respective owners. Solely for convenience, marks and trade names referred to in this prospectus may appear without the^® or TM symbols, but such references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the right of the applicable licensor to these marks and trade names. Third-party marks and trade names used herein are for informational purposes only and in no way constitute or are intended to be a commercial use of such names and marks. The use of such third-party names and marks in no way constitutes or should be construed to be an approval, endorsement or sponsorship of us, or our products or services, by the owners of such third-party names and marks.

USE OF PROCEEDS

We estimate that our net proceeds from the sale of 1,106,000 shares of our common stock in this offering will be approximately $         (or             if the underwriters exercise their over-allotment option in full),million after deducting underwriting discounts and commissions and our estimated offering expenses of approximately $            million (or approximately $            million if the underwriters exercise their over-allotment option in full). This estimate assumes a public offering price of $            per share, which is the mid-point of the offering price range indicated on the cover of this prospectus.payable by us. We will not receive any of the proceeds from anythe sale of shares of our common stock by the selling stockholder, although we will bear the costs, other than underwriting discounts and commissions, associated with the sale of these shares.stockholders.

We intend to use the net proceeds offrom this offering to invest in further improving the efficiencyfinance future acquisitions or partnerships and capacity ofalliances consistent with our machines and expanding the number of materials from which we can make products, to increase the number and locations of our PSCsbusiness strategy and for working capital and other general corporate purposes.

We continually evaluate potential acquisitions of products, technologies or businesses; however, we have no current understandings, agreements or commitments for any material acquisitions, strategic investments and/or alliances. We have not determined the specific amounts we plan to spend on any of the items listed above or the timing of these expenditures. The amounts and timing of our actual use of net proceeds will also use approximately $9.6 millionvary depending on numerous factors, including our identification of specific acquisitions, strategic investments and/or alliances, and our ability to negotiate on terms and conditions that are satisfactory to all parties involved. As a result, our management will have broad discretion in the application of the net proceeds to repay a revolving line of credit that we have with RFP (the “Rockwell Line of Credit”) for working capital. S. Kent Rockwell, our Chairman and Chief Executive Officer, is the beneficiary of the S. Kent Rockwell Revocable Trust, which is the indirect, sole stockholder of RFP. See “Certain Relationships and Related Parties.” The Rockwell Line of Credit provides for borrowing, repayment and reborrowing from time to time. While no limit is specified, borrowings are subject to RFP’s approval. Borrowings under the Rockwell Line of Credit bear interest at the rate of 8% per annum and are repayable, in whole or part, upon demand of RFP. As of December 15, 2012, we had aggregate borrowings and interest of approximately $9.6 million outstanding under the Rockwell Line of Credit. Additionally, we intend to use up to approximately $3.0 million to acquire the assets and assume certain liabilities of TMF and Lone Star, our variable interest entities.proceeds.

In the event that any net proceeds are not immediately applied, we may temporarily hold them as cash, deposit them in banks or invest them in cash equivalents or securities.

For additional information, please read “Management’s DiscussionPRICE RANGE OF OUR COMMON STOCK

Our common stock has been listed on the NASDAQ Global Market since February 7, 2013 under the symbol “XONE.” Prior to that date, there was no public market for our common stock. Shares sold in our initial public offering were priced at $18.00 per share.

On August 20, 2013, the closing price for our common stock as reported on the NASDAQ Global Market was $69.29 per share. The following table sets forth the ranges of high and Analysislow sales prices per share of Financial Conditionour common stock as reported on the NASDAQ Global Market for the period indicated. Such quotations represent inter-dealer prices without retail markup, markdown or commission and Resultsmay not necessarily represent actual transactions.

Stockholders

As of Operations — LiquidityAugust 20, 2013, there were 12 stockholders of record, which excludes stockholders whose shares were held in nominee or street name by brokers. The actual number of common stockholders is greater than the number of record holders, and Capital Resources.”includes stockholders who are beneficial owners and whose shares are held in street name by brokers and other nominees. This number of holders of record also does not include stockholders whose shares may be held in trust by other entities.

DIVIDEND POLICY

We do not anticipate that we will declare or pay regular dividends on our common stock in the foreseeable future, as we generally intend to invest any future earnings in the development and growth of our business. Future dividends, if any, will be at the discretion of our Board of Directors and will depend on many factors, including general economic and business conditions, our strategic plans, our financial results and conditions, legal requirements, any contractual obligations or limitations, and other factors that our Board of Directors deems relevant.

From the date of the Reorganization until consummation of this offering, the Class A preferred stock will accrue a dividend of 8% per annum. The Class A preferred stock is converted into common stock immediately prior to the consummation of this offering. See “Description of Capital Stock.” Immediately following this offering, there will be no Class A preferred stock outstanding.

CAPITALIZATION

The following table presents our capitalization as of SeptemberJune 30, 2012:2013:

You should read this offering to repay certain indebtedness, as described under “Use of Proceeds.” We will not receive any proceeds from the sale of shares by the selling stockholder.

This table should be read in conjunctiontogether with “Selected Consolidated Financial Data,” and our financial statements and related notes and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,Operations.” and our consolidated financial statements and related notes appearing elsewhere in this prospectus.

DILUTION

Dilution is the amount by which the offering price paid by the purchasers of the common stock to be sold in this offering will exceed the net tangible book value per share of common stock after this offering. If you invest in our common stock, your interest will be diluted to the extent of the difference between the initial public offering price per share of our common stock and the pro forma net tangible book value per share of our common stock after this offering.

After giving effect to the Reorganization, ourOur pro forma net tangible book value as of SeptemberJune 30, 20122013 was $             million, or $per share of our common stock. We calculate net tangible book value per share by calculating our total tangible assets less liabilities, and dividing it by the number of outstanding shares of our common stock.

After giving effect to the sale of 1,106,000 shares of our common stock in this offering at an assumed initiala public offering price of $         per share, which is the midpoint of the range listed on the cover page of this prospectus, and after deducting estimated underwriting discounts and commissions and estimated offering expenses payable by us, and the application of approximately $            million of the proceeds of this offering to repay certain indebtedness described in “Use of Proceeds,” our net tangible book value, which we refer to as our pro forma net tangible book value, as of June 30, 2013 would have been approximately $             million, or $             per share of our common stock.

This amount represents an immediate increase in our pro forma net tangible book value of $            per share to our existing stockholders who will receive shares in the Reorganization and an immediate dilution in our pro forma net tangible book value of $             per share to new investors purchasing shares of our common stock at the initial public offering price. We calculate dilution per share to new investors by subtracting the pro forma net tangible book value per share from the initial public offering price paid by the new investor. The following table illustrates the dilution to new investors on a per share basis:

A $1.00 increase (decrease) in the assumed initial public offering price of $            per share, which is the midpoint of the range set forth on the cover page of this prospectus, would increase (decrease) our pro forma net tangible book value as of             by             approximately $            million, the pro forma net tangible book value per share by $            per share and the dilution in pro forma net tangible book value per share to new investors by $            per share, assuming the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same and after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us.

The table below sets forth, as of                     , 2013, the number of shares of our common stock issued, the total consideration paid and the average price per share paid by our existing stockholders and our new investors in this offering after giving effect toand the issuance of             shares of common stock in this offering at the assumed initial public offering price of $         per share, before deducting underwriting discounts and commissions and our estimated offering expenses.