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INDEX TO COMBINED FINANCIAL STATEMENTS

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As filed with the Securities and Exchange Commission on March 4, 2014

Registration No. 333-          

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-1
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

MOELIS & COMPANY
(Exact Name of Registrant as Specified in Its Charter)

399 Park Avenue, 5^th Floor
New York, New York 10022
(212) 883-3800
(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)

Osamu R. Watanabe Esq.
General Counsel
Moelis & Company
399 Park Avenue, 5^th Floor
New York, New York 10022
(212) 883-3800
(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent For Service)

          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, check the following box.    o

          If this form is filed to register additional securities for an offering pursuant to Rule 462(b) 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.    o

          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.    o

          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.    o

          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.

CALCULATION OF REGISTRATION FEE

(1)

Estimated solely for the purpose of computing the amount of the registration fee pursuant to Rule 457(o) under the Securities Act.

(2)

Includes offering price of shares that the underwriters have the option to purchase.

          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 Commission, acting pursuant to said Section 8(a), may determine.

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The information in this preliminary prospectus is not complete and may be changed. We 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 are not soliciting offers to buy these securities in any jurisdiction where the offer or sale is not permitted.

PRELIMINARY PROSPECTUS (Subject to Completion)
Dated March 4, 2014

                        Shares

Class A Common Stock

        We are offering            shares of Class A common stock. This is our initial public offering and no public market currently exists for our shares. We anticipate that the initial public offering price will be between $            and $            per share.

        We intend to apply to list our Class A common stock on the New York Stock Exchange under the symbol "MC."

        We are an "emerging growth company" under applicable Securities and Exchange Commission rules and will be subject to reduced public company reporting requirements.

        Investing in our Class A common stock involves risks. See "Risk Factors" beginning on page 16.

        The Securities and Exchange Commission and state securities regulators have not approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

(1)

See "Underwriting" for a description of the compensation payable to the underwriters.

        We have granted the underwriters the right to purchase up to an additional             shares of Class A common stock at the initial public offering price less the underwriting discounts and commissions.

        The underwriters expect to deliver the shares of Class A common stock to purchasers on or about                        , 2014.

                        , 2014

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        Through and including                    , 2014 (the 25^th day after the date of this prospectus), all dealers effecting transactions in these securities, whether or not participating in this offering, may be required to deliver a prospectus. This is in addition to a dealer's obligation to deliver a prospectus when acting as an underwriter and with respect to an unsold allotment or subscription.

        We and the underwriters have not authorized anyone to provide any information or to make any representations other than those contained in this prospectus, any amendment or supplement to this prospectus or in any free writing prospectuses we have prepared. We and the underwriters take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. Neither the delivery of this prospectus nor the sale of our Class A common stock means that information contained in this prospectus is correct after the date of this prospectus. This prospectus is an offer to sell the shares offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so.

MARKET AND INDUSTRY DATA

        The industry, market and competitive position data referenced throughout this prospectus are based on research, industry and general publications, including surveys and studies conducted by third parties. Industry publications, surveys and studies generally state that they have been obtained from sources believed to be reliable. We have not independently verified such third party information. While we are not aware of any misstatements regarding any industry, market or similar data presented herein, such data involve uncertainties and are subject to change based on various factors, including those discussed under the headings "Special Note Regarding Forward-Looking Statements" and "Risk Factors" in this prospectus.

        In this prospectus, we use the term "independent investment banks" or "independent advisors" to refer to investment banks primarily focused on advisory services and that conduct limited or no commercial banking or sales and trading activities. We use the term "global independent investment banks" to refer to independent investment banks with global coverage capabilities across all major industries and regions. We consider the global independent investment banks to be our publicly-traded peers, Evercore Partners Inc., Greenhill & Co., Inc., Lazard Ltd, and us.

Map Legend

•Moelis & Company office

/*\

Strategic alliance

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RISK FACTORS

        Investing in our Class A common stock involves a high degree of risk. You should carefully consider the following risks and all other information contained in this prospectus, including our financial statements and the related notes thereto, before investing in our Class A common stock. The risks and uncertainties described below are not the only ones we face. Additional risks and uncertainties that we are unaware of, or that we currently believe are not material, also may become important factors that affect us. If any of the following risks materialize, our business, financial condition and results of operations could be materially adversely affected. In that case, the trading price of our Class A common stock could decline, and you may lose some or all of your investment.

Risks Related to Our Business

Our future growth will depend on, among other things, our ability to successfully identify, recruit and develop talent and will require us to commit additional resources.

        We have experienced rapid growth over the past several years, which may be difficult to sustain at the same rate. Our future growth will depend on, among other things, our ability to successfully identify and recruit individuals and teams to join our firm. It typically takes time for these professionals to become profitable and effective. During that time, we may incur significant expenses and expend significant time and resources toward training, integration and business development aimed at developing this new talent. If we are unable to recruit and develop profitable professionals, we will not be able to implement our growth strategy and our financial results could be materially adversely affected.

        In addition, sustaining growth will require us to commit additional management, operational and financial resources and to maintain appropriate operational and financial systems to adequately support expansion, especially in instances where we open new offices that may require additional resources before they become profitable. See "—Our growth strategy may involve opening or acquiring new offices and expanding internationally and would involve hiring new Managing Directors and other senior professionals for these offices, which would require substantial investment by us and could materially and adversely affect our operating results." There can be no assurance that we will be able to manage our expanding operations effectively, and any failure to do so could materially adversely affect our ability to grow revenue and control our expenses.

Changing market conditions can adversely affect our business in many ways, including by reducing the volume of the transactions involving our business, which could materially reduce our revenue.

        As a financial services firm, we are materially affected by conditions in the global financial markets and economic conditions throughout the world. For example, our revenue is directly related to the volume and value of the transactions in which we are involved. During periods of unfavorable market or economic conditions, the volume and value of M&A transactions may decrease, thereby reducing the demand for our M&A advisory services and increasing price competition among financial services companies seeking such engagements. In addition, during periods of strong market and economic conditions, the volume and value of recapitalization and restructuring transactions may decrease, thereby reducing the demand for our recapitalization and restructuring advisory services and increasing price competition among financial services companies seeking such engagements. Our results of operations would be adversely affected by any such reduction in the volume or value of such advisory transactions. Further, in the period following an economic downturn, the volume and value of M&A transactions typically takes time to recover and lags a recovery in market and economic conditions.

        Our profitability may also be adversely affected by our fixed costs and the possibility that we would be unable to scale back other costs within a time frame sufficient to match any decreases in revenue relating to changes in market and economic conditions. The future market and economic climate may

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deteriorate because of many factors beyond our control, including rising interest rates or inflation, terrorism or political uncertainty.

Our revenue in any given period is dependent on the number of fee-paying clients in such period, and a significant reduction in the number of fee-paying clients in any given period could reduce our revenue and adversely affect our operating results in such period.

        Our revenue in any given period is dependent on the number of fee-paying clients in such period. We had 109 clients and 107 clients paying fees equal to or greater than $1 million in 2013 and 2012, respectively. We may lose clients as a result of the sale or merger of a client, a change in a client's senior management, competition from other financial advisors and financial institutions and other causes. A significant reduction in the number of fee-paying clients in any given period could reduce our revenue and adversely affect our operating results in such period.

Our ability to retain our Managing Directors and our other professionals, including our executive officers, is critical to the success of our business.

        Our future success depends to a substantial degree on our ability to retain qualified professionals within our organization, including our Managing Directors. However, we may not be successful in our efforts to retain the required personnel as the market for qualified investment bankers is extremely competitive. Our investment bankers possess substantial experience and expertise and have strong relationships with our advisory clients. As a result, the loss of these professionals could jeopardize our relationships with clients and result in the loss of client engagements. For example, if any of our Managing Directors or other senior professionals, including our executive officers, or groups of professionals, were to join or form a competing firm, some of our current clients could choose to use the services of that competitor rather than our services. There is no guarantee that our compensation and non-competition arrangements with our Managing Directors provide sufficient incentives or protections to prevent our Managing Directors from resigning to join our competitors. In addition, some of our competitors have more resources than us which may allow them to attract some of our existing employees through compensation or otherwise. The departure of a number of Managing Directors or groups of professionals could have a material adverse effect on our business and our profitability.

        We depend on the efforts and reputations of Mr. Moelis and our other executive officers. Our senior leadership team's reputations and relationships with clients and potential clients are critical elements in the success of our business. The loss of the services of any of them, in particular Mr. Moelis, could have a material adverse effect on our business, including our ability to attract clients.

Substantially all of our revenue is derived from advisory fees. As a result, our revenue and profits are highly volatile on a quarterly basis and may cause the price of our Class A common stock to fluctuate and decline.

        Our revenue and profits are highly volatile. We derive substantially all of our revenue from advisory fees, generally from a limited number of engagements that generate significant fees at key transaction milestones, such as closing, the timing of which is outside of our control. We expect that we will continue to rely on advisory fees for most of our revenue for the foreseeable future. Accordingly, a decline in our advisory engagements or the market for advisory services would adversely affect our business. In addition, our financial results will likely fluctuate from quarter to quarter based on the timing of when fees are earned, and high levels of revenue in one quarter will not necessarily be predictive of continued high levels of revenue in future periods. Because we lack other, more stable, sources of revenue, which could moderate some of the volatility in our advisory revenue, we may experience greater variations in our revenue and profits than other larger, more diversified competitors in the financial services industry. Fluctuations in our quarterly financial results could, in turn, lead to

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large adverse movements in the price of our common stock or increased volatility in our stock price generally.

        Because in many cases we are not paid until the successful consummation of the underlying transaction, our revenue is highly dependent on market conditions and the decisions and actions of our clients, interested third parties and governmental authorities. For example, we may be engaged by a client in connection with a sale or divestiture, but the transaction may not occur or be consummated because, among other things, anticipated bidders may not materialize, no bidder is prepared to pay our client's price or because our client's business experiences unexpected operating or financial problems. We may be engaged by a client in connection with an acquisition, but the transaction may not occur or be consummated for a number of reasons, including because our client may not be the winning bidder, failure to agree upon final terms with the counterparty, failure to obtain necessary regulatory consents or board or stockholder approvals, failure to secure necessary financing, adverse market conditions or because the target's business experiences unexpected operating or financial problems. In these circumstances, we often do not receive significant advisory fees, despite the fact that we have devoted considerable resources to these transactions.

        In addition, we face the risk that certain clients may not have the financial resources to pay our agreed-upon advisory fees. Certain clients may also be unwilling to pay our advisory fees in whole or in part, in which case we may have to incur significant costs to bring legal action to enforce our engagement agreement to obtain our advisory fees.

Our joint ventures, strategic investments and acquisitions may result in additional risks and uncertainties in our business.

        In addition to recruiting and internal expansion, we may grow our core business through joint ventures, strategic investments or acquisitions.

        In the case of joint ventures, such as our 50% investment in our Australian joint venture, Moelis Australia Holdings Pty Ltd (the "Australian JV"), we are subject to additional risks and uncertainties relating to governance and controls, in that we may be dependent upon, and subject to liability, losses or reputational damage relating to personnel, controls and systems that are not fully under our control. In addition, disagreements between us and our joint venture partners may negatively impact our business. Although our Australian JV must abide by certain market risk limits approved by us with respect to its trading activities, there is a risk that such limits will be insufficient to protect us against significant losses. In addition, investments made by our Australian JV could be unprofitable.

        In the event we make further strategic investments or acquisitions, we would face numerous risks and would be presented with financial, managerial and operational challenges, including the difficulty of integrating personnel, financial, accounting, technology and other systems and management controls.

If the number of debt defaults, bankruptcies or other factors affecting demand for our recapitalization and restructuring advisory services declines, our recapitalization and restructuring business could suffer.

        We provide various financial recapitalization and restructuring and related advice to companies in financial distress or to their creditors or other stakeholders. A number of factors affect demand for these advisory services, including general economic conditions, the availability and cost of debt and equity financing, governmental policy and changes to laws, rules and regulations, including those that protect creditors. In addition, providing recapitalization and restructuring advisory services entails the risk that the transaction will be unsuccessful, takes considerable time and can be subject to a bankruptcy court's discretionary power to disallow or discount our fees. If the number of debt defaults, bankruptcies or other factors affecting demand for our recapitalization and restructuring advisory services declines, our recapitalization and restructuring business would be adversely affected.

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Our failure to deal appropriately with actual, potential or perceived conflicts of interest could damage our reputation and materially adversely affect our business.

        We confront actual, potential or perceived conflicts of interest in our business. For instance, we face the possibility of an actual, potential or perceived conflict of interest where we represent a client on a transaction in which an existing client is a party. We may be asked by two potential clients to act on their behalf on the same transaction, including two clients as potential buyers in the same acquisition transaction, and we may act for both clients if both clients agree to us doing so. In each of these situations, we face the risk that our current policies, controls and procedures do not timely identify or appropriately manage such conflicts of interest.

        It is possible that actual, potential or perceived conflicts could give rise to client dissatisfaction, litigation or regulatory enforcement actions. Appropriately identifying and managing actual or perceived conflicts of interest is complex and difficult, and our reputation could be damaged if we fail, or appear to fail, to deal appropriately with one or more potential or actual conflicts of interest. Regulatory scrutiny of, or litigation in connection with, conflicts of interest could have a material adverse effect on our reputation which could materially adversely affect our business in a number of ways, including a reluctance of some potential clients and counterparties to do business with us.

Employee misconduct, which is difficult to detect and deter, could harm us by impairing our ability to attract and retain clients and by subjecting us to legal liability and reputational harm.

        There is a risk that our employees could engage in misconduct that would adversely affect our business. For example, our business often requires that we deal with confidential matters of great significance to our clients. If our employees were to improperly use or disclose confidential information provided by our clients, we could be subject to regulatory sanctions and suffer serious harm to our reputation, financial position, current client relationships and ability to attract future clients. It is not always possible to deter employee misconduct, and the precautions we take to detect and prevent misconduct may not be effective in all cases. If our employees engage in misconduct, our business could be materially adversely affected.

We may face damage to our professional reputation if our services are not regarded as satisfactory or for other reasons.

        As an advisory service firm, we depend to a large extent on our relationships with our clients and reputation for integrity and high-caliber professional services to attract and retain clients. As a result, if a client is not satisfied with our services, it may be more damaging in our business than in other businesses.

We face strong competition from other financial advisory firms, many of which have the ability to offer clients a wider range of products and services than those we can offer, which could cause us to fail to win advisory mandates and subject us to pricing pressures that could materially adversely affect our revenue and profitability.

        The financial services industry is intensely competitive, and we expect it to remain so. Our competitors are other investment banking and financial advisory firms. We compete on both a global and a regional basis, and on the basis of a number of factors, including depth of client relationships, industry knowledge, transaction execution skills, our range of products and services, innovation, reputation and price. In addition, in our business there are usually no long-term contracted sources of revenue. Each revenue-generating engagement typically is separately solicited, awarded and negotiated.

        We have experienced intense competition over obtaining advisory mandates in recent years, and we may experience further pricing pressures in our business in the future as some of our competitors may seek to obtain increased market share by reducing fees.

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        Our primary competitors are large financial institutions, many of which have far greater financial and other resources than us and, unlike us, have the ability to offer a wider range of products, from loans, deposit taking and insurance to brokerage and trading, which may enhance their competitive position. They also regularly support investment banking, including financial advisory services, with commercial lending and other financial services and products in an effort to gain market share, which puts us at a competitive disadvantage and could result in pricing pressures or loss of opportunities, which could materially adversely affect our revenue and profitability. In addition, we may be at a competitive disadvantage with regard to certain of our competitors who are able to and often do, provide financing or market making services that are often a crucial component of the types of transactions on which we advise.

        In addition to our larger competitors, over the last few years a number of independent investment banks that offer independent advisory services have emerged, with several showing rapid growth. As these independent firms or new entrants into the market seek to gain market share there could be pricing pressures, which would adversely affect our revenues and earnings.

As a member of the financial services industry, we face substantial litigation risks.

        Our role as advisor to our clients on important transactions involves complex analysis and the exercise of professional judgment, including rendering "fairness opinions" in connection with mergers and other transactions. Our activities may subject us to the risk of significant legal liabilities to our clients and affected third parties, including shareholders of our clients who could bring securities class actions against us. In recent years, the volume of claims and amount of damages claimed in litigation and regulatory proceedings against financial services companies have been increasing. These risks often may be difficult to assess or quantify and their existence and magnitude often remain unknown for substantial periods of time. Our engagements typically include broad indemnities from our clients and provisions to limit our exposure to legal claims relating to our services, but these provisions may not protect us in all cases, including when a client does not have the financial capacity to pay under the indemnity. As a result, we may incur significant legal expenses in defending against or settling litigation. In addition, we may have to spend a significant amount to adequately insure against these potential claims. Substantial legal liability or significant regulatory action against us could have material adverse financial effects or cause significant reputational harm to us, which could seriously harm our business prospects.

Our management has not previously managed a public company.

        Our management team has historically operated our business as a privately-owned company. The individuals who now constitute our management have not previously managed a publicly-traded company.

        Compliance with public company requirements will place significant additional demands on our management and will require us to enhance our investor relations, legal, financial reporting and corporate communications functions. These additional efforts may strain our resources and divert management's attention from other business concerns, which could adversely affect our business and profitability.

        In addition, the reorganization to take place in connection with the consummation of this offering will involve separating our advisory business from the asset management business of Old Holdings. These two businesses have historically utilized common management and operational structures, including facilities and technology platforms as well as legal, compliance, marketing and other support personnel and senior management oversight. The process of separating these businesses, and of operating our advisory business on a stand-alone basis, may result in increased costs and inefficiencies

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and other impediments to the regular operations of our business, the occurrence of any of which could adversely affect our business and profitability.

Extensive and evolving regulation of our business and the business of our clients exposes us to the potential for significant penalties and fines due to compliance failures, increases our costs and may result in limitations on the manner in which our business is conducted.

        As a participant in the financial services industry, we are subject to extensive regulation in the U.S. and internationally. We are subject to regulation by governmental and self-regulatory organizations in the jurisdictions in which we operate. As a result of market volatility and disruption in recent years, the U.S. and other governments have taken unprecedented steps to try to stabilize the financial system including providing assistance to financial institutions and taking certain regulatory actions. The full extent of the effects of these actions and of legislative and regulatory initiatives (including the Dodd-Frank Wall Street Reform and Consumer Protection Act) effected in connection with, and as a result of, such extraordinary disruption and volatility is uncertain, both as to the financial markets and participants in general, and as to us in particular.

        Our ability to conduct business and our operating results, including compliance costs, may be adversely affected as a result of any new requirements imposed by the Securities and Exchange Commission ("SEC"), FINRA or other U.S. or foreign governmental regulatory authorities or self-regulatory organizations that regulate financial services firms or supervise financial markets. We may be adversely affected by changes in the interpretation or enforcement of existing laws and rules by these governmental authorities and self-regulatory organizations. In addition, some of our clients or prospective clients may adopt policies that exceed regulatory requirements and impose additional restrictions affecting their dealings with us. Accordingly, we may incur significant costs to comply with U.S. and international regulation. In addition, new laws or regulations or changes in enforcement of existing laws or regulations applicable to our clients may adversely affect our business. For example, changes in antitrust enforcement could affect the level of M&A activity and changes in applicable regulations could restrict the activities of our clients and their need for the types of advisory services that we provide to them.

        Our failure to comply with applicable laws or regulations could result in adverse publicity and reputational harm as well as fines, suspensions of personnel or other sanctions, including revocation of the registration of us or any of our subsidiaries as a financial adviser and could impair executive retention or recruitment. In addition, any changes in the regulatory framework could impose additional expenses or capital requirements on us, result in limitations on the manner in which our business is conducted, have an adverse impact upon our financial condition and business and require substantial attention by senior management. In addition, our business is subject to periodic examination by various regulatory authorities, and we cannot predict the outcome of any such examinations.

Our business is subject to various operational risks.

        We face various operational risks related to our business on a day-to-day basis. We rely heavily on financial, accounting, communication and other information technology systems, and the people who operate them. These systems, including the systems of third parties on whom we rely, may fail to operate properly or become disabled as a result of tampering or a breach of our network security systems or otherwise, including for reasons beyond our control.

        Our clients typically provide us with sensitive and confidential information. We are dependent on information technology networks and systems to securely process, transmit and store such information and to communicate among our locations around the world and with our clients, alliance partners and vendors. We may be subject to attempted security breaches and cyber-attacks and, while none have had a material impact to date, a successful breach could lead to shutdowns or disruptions of our systems or

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third-party systems on which we rely and potential unauthorized disclosure of sensitive or confidential information. Breaches of our or third-party network security systems on which we rely could involve attacks that are intended to obtain unauthorized access to our proprietary information, destroy data or disable, degrade or sabotage our systems, often through the introduction of computer viruses, cyber-attacks and other means and could originate from a wide variety of sources, including unknown third parties outside the firm. Although we take various measures to ensure the integrity of our and third-party systems on which we rely, there can be no assurance that these measures will provide adequate protection. If our or third-party systems on which we rely are compromised, do not operate properly or are disabled, we could suffer a disruption of our business, financial losses, liability to clients, regulatory sanctions and damage to our reputation.

        We operate a business that is highly dependent on information systems and technology. Any failure to keep accurate books and records can render us liable to disciplinary action by governmental and self-regulatory authorities, as well as to claims by our clients. We rely on third-party service providers for certain aspects of our business. Any interruption or deterioration in the performance of these third parties or failures of their information systems and technology could impair our operations, affect our reputation and adversely affect our business.

        In addition, a disaster or other business continuity problem, such as a pandemic, other man-made or natural disaster or disruption involving electronic communications or other services used by us or third parties with whom we conduct business, could lead us to experience operational challenges, and our inability to timely and successfully recover could materially disrupt our business and cause material financial loss, regulatory actions, reputational harm or legal liability.

We may not be able to generate sufficient cash in the future to service any future indebtedness.

        Our ability to make scheduled payments on or to refinance any future debt obligations depends on our financial condition and operating performance. We cannot provide assurance that we will maintain a level of cash flows from operating activities sufficient to permit us to pay the principal of, and interest on, any future indebtedness. If our cash flows and capital resources are insufficient to fund any future debt service obligations, we may be forced to reduce or delay investments and capital expenditures, or to sell assets, seek additional capital or restructure or refinance such indebtedness.

Our international operations are subject to certain risks, which may affect our revenue.

        In 2013, we earned approximately 19% of our revenues from our international operations. We intend to grow our non-U.S. business, and this growth is important to our overall success. In addition, many of our larger clients are non-U.S. entities seeking to enter into transactions involving U.S. businesses. Our international operations carry special financial and business risks, which could include the following:

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greater difficulties in managing and staffing foreign operations;



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language and cultural differences;



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fluctuations in foreign currency exchange rates that could adversely affect our results;



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unexpected changes in trading policies, regulatory requirements, tariffs and other barriers;



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longer transaction cycles;



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higher operating costs;



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adverse consequences or restrictions on the repatriation of earnings;



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potentially adverse tax consequences, such as trapped foreign losses;

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less stable political and economic environments; and



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civil disturbances or other catastrophic events that reduce business activity.

        If our international business increases relative to our total business, these factors could have a more pronounced effect on our operating results.

Our growth strategy may involve opening or acquiring new offices and expanding internationally and would involve hiring new Managing Directors and other senior professionals for these offices, which would require substantial investment by us and could materially and adversely affect our operating results.

        Our ability to grow our advisory business organically depends in part on our ability to open or acquire new offices, expand internationally and hire new Managing Directors and other senior professionals for these offices. We may not be successful in any efforts to open new offices, expand internationally or hire new Managing Directors and other senior professionals for these offices. The costs of opening a new office, expanding internationally and hiring the necessary personnel to staff the office are substantial. If we are not successful in these efforts, we may not be able to recover our investments or our substantial cost outlays, and new international operations may not achieve profitability.

We may enter into new lines of business which may result in additional risks and uncertainties in our business.

        We currently generate substantially all of our revenue from advisory transactions. However, we may grow our business by entering into new lines of business. To the extent we enter into new lines of business, we will face numerous risks and uncertainties, including risks associated with actual or perceived conflicts of interest because we would no longer be limited to the advisory business, the possibility that we have insufficient expertise to engage in such activities profitably or without incurring inappropriate amounts of risk, the required investment of capital and other resources and the loss of clients due to the perception that we are no longer focusing on our core business.

        Entry into certain lines of business may subject us to new laws and regulations with which we are not familiar, or from which we are currently exempt, and may lead to increased litigation and regulatory risk. In addition, certain aspects of our cost structure, such as costs for compensation, occupancy and equipment rentals, communication and information technology services, and depreciation and amortization will be largely fixed, and we may not be able to timely adjust these costs to match fluctuations in revenue related to our entering into new lines of business. If a new business generates insufficient revenues or if we are unable to efficiently manage our expanded operations, our results of operations could be materially adversely affected.

Fluctuations in foreign currency exchange rates could adversely affect our results.

        Because our financial statements are denominated in U.S. dollars and we receive a portion of our net revenue in other currencies (including euros and pound sterling), we are exposed to fluctuations in foreign currencies. In addition, we pay certain of our expenses in such currencies. We have not entered into any transactions to hedge our exposure to these foreign exchange fluctuations through the use of derivative instruments or otherwise. An appreciation or depreciation of any of these currencies relative to the U.S. dollar would result in an adverse or beneficial impact, respectively, to our financial results.

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The cost of compliance with international broker-dealer, employment, labor, benefits and tax regulations may adversely affect our business and hamper our ability to expand internationally.

        Since we operate our business both in the U.S. and internationally, we are subject to many distinct broker-dealer, employment, labor, benefits and tax laws in each country in which we operate, including regulations affecting our employment practices and our relations with our employees and service providers. If we are required to comply with new regulations or new interpretations of existing regulations, or if we are unable to comply with these regulations or interpretations, our business could be adversely affected or the cost of compliance may make it difficult to expand into new international markets. Additionally, our competitiveness in international markets may be adversely affected by regulations requiring, among other things, the awarding of contracts to local contractors, the employment of local citizens and/or the purchase of services from local businesses or favoring or requiring local ownership.

Risks Related to Our Organizational Structure

Moelis & Company's only assets after completion of this offering will be its partnership interests in Group LP, its equity interest in the sole general partner of Group LP, Moelis & Company Group GP LLC, and its interests in its subsidiaries, and Moelis & Company is accordingly dependent upon distributions from Group LP to pay dividends, taxes and other expenses.

        Moelis & Company will be a holding company, and its only assets will be its partnership interests in Group LP, its equity interest in the sole general partner of Group LP, Moelis & Company Group GP LLC, and its interests in its subsidiaries. Moelis & Company has no independent means of generating revenue. Moelis & Company intends to cause Group LP to make distributions to its partners in an amount sufficient to cover all applicable taxes payable, other expenses and dividends, if any, declared by us.

        Group LP is generally prohibited under Delaware law from making a distribution to a partner to the extent that, at the time of the distribution, after giving effect to the distribution, liabilities of Group LP (with certain exceptions) exceed the fair value of its assets. Furthermore, certain subsidiaries of Group LP may be subject to similar legal limitations on their ability to make distributions to Group LP. Moreover, our regulated subsidiaries may be subject to regulatory capital requirements that limit the distributions that may be made by those subsidiaries.

        Deterioration in the financial condition, earnings or cash flow of Group LP and its subsidiaries for any reason could limit or impair their ability to pay such distributions. Additionally, to the extent that Moelis & Company requires funds and Group LP is restricted from making such distributions under applicable law or regulation or under the terms of financing arrangements, or is otherwise unable to provide such funds, our liquidity and financial condition could be materially adversely affected.

We will be required to pay our Managing Directors for certain tax benefits we may claim as a result of the tax basis step-up we receive in connection with this offering and related transactions. In certain circumstances, payments under the tax receivable agreement may be accelerated and/or significantly exceed the actual tax benefits we realize.

        On the date of this offering, we will be treated for U.S. federal income tax purposes as having directly purchased Class A partnership units in Group LP from the existing unitholders. In the future, additional Group LP Class A partnership units may be exchanged for shares of Class A common stock. See "Organizational Structure—Exchange Rights." Both this initial purchase and these additional exchanges may result in increases in the tax basis of the assets of Group LP that otherwise would not have been available. Such increases in tax basis are likely to increase (for tax purposes) depreciation and amortization deductions and therefore reduce the amount of income tax we would otherwise be required to pay in the future. These increases in tax basis may also decrease gain (or increase loss) on

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future dispositions of certain capital assets to the extent the increased tax basis is allocated to those capital assets. The Internal Revenue Service (the "IRS") may challenge all or part of these tax basis increases, and a court could sustain such a challenge.

        We intend to enter into a tax receivable agreement with our Managing Directors that will provide for the payment by us to our Managing Directors of 85% of the amount of cash savings, if any, in U.S. federal, state and local income tax or franchise tax that we actually realize as a result of (a) the increases in tax basis attributable to our Managing Directors and (b) tax benefits related to imputed interest deemed to be paid by us as a result of this tax receivable agreement. See "Organizational Structure—Tax Receivable Agreement." While the actual increase in tax basis, as well as the amount and timing of any payments under the tax receivable agreement, will vary depending upon a number of factors, including the timing of exchanges, the price of shares of our Class A common stock at the time of the exchange, the extent to which such exchanges are taxable, and the amount and timing of our income, we expect that, as a result of the size of the increases in the tax basis of the tangible and intangible assets of Group LP attributable to our interests in Group LP, during the expected term of the tax receivable agreement, the payments that we may make to our Managing Directors could be substantial.

        Although we are not aware of any issue that would cause the IRS to challenge a tax basis increase, our Managing Directors generally will not reimburse us for any payments that may previously have been made under the tax receivable agreement. As a result, in certain circumstances we could make payments to the Managing Directors under the tax receivable agreement in excess of our cash tax savings. Our ability to achieve benefits from any tax basis increase, and the payments to be made under the tax receivable agreement, will depend upon a number of factors, as discussed above, including the timing and amount of our future income.

        In addition, the tax receivable agreement provides that, upon a merger, asset sale or other form of business combination or certain other changes of control or if, at any time, we elect an early termination of the tax receivable agreement, our (or our successor's) obligations with respect to exchanged or acquired Class A partnership units (whether exchanged or acquired before or after such change of control or early termination) would be based on certain assumptions, including that we would have sufficient taxable income to fully utilize the deductions arising from the increased tax deductions and tax basis and other benefits related to entering into the tax receivable agreement, and, in the case of certain early termination elections, that any Class A partnership units that have not been exchanged will be deemed exchanged for the market value of the Class A common stock at the time of termination. Consequently, it is possible, in these circumstances also, that the actual cash tax savings realized by us may be significantly less than the corresponding tax receivable agreement payments.

If Moelis & Company were deemed an "investment company" under the Investment Company Act of 1940 as a result of its ownership of Group LP, applicable restrictions could make it impractical for us to continue our business as contemplated and could have a material adverse effect on our business.

        If Moelis & Company were to cease participation in the management of Group LP, its interests in Group LP could be deemed an "investment security" for purposes of the Investment Company Act of 1940 (the "1940 Act"). Generally, a person is deemed to be an "investment company" if it owns investment securities having a value exceeding 40% of the value of its total assets (exclusive of U.S. government securities and cash items), absent an applicable exemption. Following this offering, Moelis & Company will have no assets other than its partnership interests in Group LP and its equity interest in the sole general partner of Group LP, Moelis & Company Group GP LLC and its interests in its subsidiaries. A determination that this interest was an investment security could result in Moelis & Company being an investment company under the 1940 Act and becoming subject to the registration and other requirements of the 1940 Act. We intend to conduct our operations so that we will not be deemed an investment company. However, if we were to be deemed an investment

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company, restrictions imposed by the 1940 Act, including limitations on our capital structure and our ability to transact with affiliates, could make it impractical for us to continue our business as contemplated and have a material adverse effect on our business and the price of our Class A common stock.

We and Old Holdings will enter into various arrangements, including a master separation agreement, which will contain cross-indemnification obligations of us and Old Holdings.

        The master separation agreement that we intend to enter into with Old Holdings will provide, among other things, that Old Holdings generally will indemnify us for losses that we incur arising out of, or relating to, the businesses conducted by Old Holdings and losses that we incur arising out of, or relating to, Old Holdings' breach of the master separation agreement. In addition, we generally will indemnify Old Holdings for losses that Old Holdings incurs arising out of, or relating to, our business and losses Old Holdings' incurs arising out of, or relating to, our breach of the master separation agreement. We may not be able to recover any or all of the amount of indemnified losses from Old Holdings should it be financially unable to perform under its indemnification obligations. In addition, we may be required to make substantial payments under our indemnity obligations to Old Holdings, which could materially adversely affect our results of operations.

The use of the "Moelis" brand name by Old Holdings and its subsidiaries may expose us to reputational harm that could adversely affect our business should they take actions that damage the brand name.

        After the separation transaction, Old Holdings will operate as a separate legal entity, and we will license to Old Holdings and its subsidiaries the use of the "Moelis" brand name for certain purposes, including in connection with asset management activities. As Old Holdings and its subsidiaries historically have and will continue to use the "Moelis" brand name, and because after the separation transactions we will not control these entities, there is a risk of reputational harm to us if Old Holdings and its subsidiaries have, or in the future, were to, among other things, engage in poor business practices, experience adverse results or otherwise damage the reputational value of the "Moelis" brand name. These risks could adversely affect our revenue and our business prospects.

Risks Related to Our Class A Common Stock and this Offering

Control by Mr. Moelis of the voting power in Moelis & Company may give rise to actual or perceived conflicts of interests.

        Upon completion of this offering, Moelis & Company will be controlled by Mr. Moelis, through his control of Partner Holdings. Mr. Moelis' interests may differ from those of other stockholders. Upon completion of this offering, Mr. Moelis will control approximately        % of the voting interest in Moelis & Company, (or        % if the underwriters exercise their option to purchase additional shares in full), primarily through his control of Partner Holdings, which will hold all outstanding Class B common stock upon completion of this offering. The shares of Class B common stock will entitle Partner Holdings to (i) for so long as the Class B Condition is satisfied, ten votes per share and (ii) after the Class B Condition ceases to be satisfied, one vote per share. See "Organizational Structure—Amended and Restated Limited Partnership Agreement of Group LP—Voting and Economic Rights." In addition, in connection with the completion of this offering, Moelis & Company will enter into a stockholders agreement with Partner Holdings, pursuant to which, for so long as the Class B Condition is satisfied, Partner Holdings will have certain approval rights over certain transactions. See "Organizational Structure—Rights of Partner Holdings and Stockholders Agreement." As a result, because Mr. Moelis will have a majority of the voting power in Moelis & Company and our amended and restated certificate of incorporation to be in effect upon consummation of this offering will not provide for cumulative voting, he will have the ability to elect all of the members of our board of directors and thereby to control our management and affairs, including determinations

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with respect to acquisitions, dispositions, borrowings, issuances of Class A common stock or other securities, and the declaration and payment of dividends. Mr. Moelis will be able to determine the outcome of all matters requiring stockholder approval and will be able to cause or prevent a change of control of Moelis & Company or a change in the composition of our board of directors and could preclude any unsolicited acquisition of Moelis & Company. Mr. Moelis' voting control could deprive our stockholders of an opportunity to receive a premium for their Class A common stock as part of a sale of Moelis & Company and might ultimately affect the market price of our Class A common stock. As a result of the control exercised by Mr. Moelis over us, none of our agreements with him have been negotiated on "arm's length" terms. We cannot assure you that we would not have received more favorable terms from an unaffiliated party.

Upon the listing of our shares on the New York Stock Exchange, we will be a "controlled company" within the meaning of the rules of the New York Stock Exchange and, as a result, will qualify for, and intend to rely on, exemptions from certain corporate governance requirements. You will not have the same protections afforded to stockholders of companies that are subject to such requirements.

        Upon completion of this offering, Mr. Moelis, through his control of Partner Holdings, will hold more than 50% of the voting power of our shares eligible to vote. As a result, we will be a "controlled company" under the rules of the New York Stock Exchange ("NYSE"). Under these rules, a company of which more than 50% of the voting power in the election of directors is held by an individual, group or another company is a "controlled company" and may elect not to comply with certain corporate governance requirements, including the requirements that (i) a majority of the board of directors consist of independent directors and (ii) that the board of directors have compensation and nominating and corporate governance committees composed entirely of independent directors.

        For at least some period following this offering, we intend to utilize these exemptions. As a result, immediately following this offering we will not have a majority of independent directors on our board of directors. Accordingly, although we may transition to a board with a majority of independent directors prior to the time we cease to be a "controlled company," for such period of time you will not have the same protections afforded to stockholders of companies that are subject to all of the corporate governance requirements set by the NYSE. In the event that we cease to be a "controlled company" and our shares continue to be listed on the NYSE, we will be required to comply with these provisions within the applicable transition periods. These exemptions do not modify the independence requirements for our audit committee, and we intend to comply with the applicable requirements of the SEC and the NYSE with respect to our audit committee within the applicable time frame.

We are an emerging growth company, and any decision on our part to comply only with certain reduced reporting and disclosure requirements applicable to emerging growth companies could make our common stock less attractive to investors.

        We are an emerging growth company and, for as long as we continue to be an emerging growth company, we may choose to take advantage of exemptions from various reporting requirements applicable to other public companies but not to "emerging growth companies," including, but not limited to, not being required to have our independent registered public accounting firm audit our internal control over financial reporting under Section 404 of the Sarbanes-Oxley Act, reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. We could be an emerging growth company for up to five years following the completion of this offering. We will cease to be an emerging growth company upon the earliest of: (i) the end of the fiscal year following the fifth anniversary of this offering, (ii) the first fiscal year after our annual gross revenues are $1.0 billion or more, (iii) the date on which we have, during the previous three-year period, issued

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more than $1.0 billion in non-convertible debt securities or (iv) the end of any fiscal year in which the market value of our common stock held by non-affiliates exceeded $700 million as of the end of the second quarter of that fiscal year. We cannot predict if investors will find our common stock less attractive if we choose to rely on these exemptions. If some investors find our common stock less attractive as a result of any choices to reduce future disclosure, there may be a less active trading market for our common stock, and the price of our common stock may be more volatile.

        Under the JOBS Act, emerging growth companies can also delay adopting new or revised accounting standards until such time as those standards apply to private companies. We have irrevocably elected not to avail ourselves of this accommodation, and, therefore, we will be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.

You will experience immediate and substantial dilution in the book value of your Class A common stock.

        The initial public offering price of our Class A common stock is substantially higher than the net tangible book value per share of our Class A common stock. Net tangible book value represents the amount of our tangible assets less total liabilities. As a result, you will incur immediate dilution of $            per share (based on an initial public offering price of $            per share, the mid-point of the range on the cover of this prospectus). For more information, see "Dilution."

There may not be an active trading market for shares of our Class A common stock, which may cause our Class A common stock to trade at a discount from its initial offering price and make it difficult to sell the shares you purchase.

        Prior to this offering, there has been no public trading market for shares of our Class A common stock. It is possible that, after this offering, an active trading market will not develop or continue, which would make it difficult for you to sell your shares of Class A common stock at an attractive price or at all. The initial public offering price per share of our Class A common stock will be determined by agreement among us and the representatives of the underwriters, and may not be indicative of the price at which the shares of our Class A common stock will trade in the public market after this offering.

The historical financial information in this prospectus may not permit you to predict our costs of operations.

        The historical financial information in this prospectus does not reflect the added costs we expect to incur as a public company, including costs related to public company reporting, investor relations and compliance with the Sarbanes-Oxley Act of 2002. As a result of these matters, among others, it may be difficult for investors to compare our future results to historical results or to evaluate our relative performance or trends in our business. For more information on our historical financial information, see "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the historical financial statements included elsewhere in this prospectus.

If securities analysts do not publish research or reports about our business or if they downgrade our Company or our sector, the price of our Class A common stock could decline.

        The trading market for our Class A common stock will depend in part on the research and reports that industry or financial analysts publish about us or our business. We do not control these analysts. Furthermore, if one or more of the analysts who do cover us downgrades our Company or our industry, or the stock of any of our competitors, the price of our Class A common stock could decline. If one or more of these analysts ceases coverage of our Company, we could lose visibility in the market, which in turn could cause the price of our Class A common stock to decline.

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Our share price may decline due to the large number of shares eligible for future sale and for exchange.

        The market price of our Class A common stock could decline as a result of sales of a large number of shares of Class A common stock in the market after the offering or the perception that such sales could occur. These sales, or the possibility that these sales may occur, also might make it more difficult for us to sell equity securities in the future at a time and at a price that we deem appropriate. After the consummation of this offering, we will have outstanding shares of Class A common stock. This number primarily comprises the shares of our Class A common stock that we are selling in this offering, which may be resold immediately in the public market. See "Shares Eligible for Future Sale."

        We have agreed with the underwriters not to dispose of or hedge any of our Class A common stock, subject to specified exceptions, during the period from the date of this prospectus continuing through the date that is 180 days after the date of this prospectus, except with the prior written consent of the representatives of the underwriters. Subject to these agreements, we may issue and sell in the future additional shares of Class A common stock.

        In addition, the existing Group LP Class A partnership unitholders (including certain Managing Directors) will, at the time of this offering, own an aggregate of                     Class A partnership units in Group LP. Our amended and restated certificate of incorporation will allow the exchange of Class A partnership units in Group LP (other than those held by us) for shares of our Class A common stock on a one-for-one basis, subject to customary conversion rate adjustments for stock splits, stock dividends and reclassifications. Our directors and executive officers and certain of their affiliates have agreed with the underwriters not to dispose of or hedge any of our Class A common stock, subject to specified exceptions, during the period from the date of this prospectus continuing through the date that is 180 days after the date of this prospectus, except with the prior written consent of the representatives of the underwriters. After the expiration of the 180-day lock-up period, the shares of Class A common stock (including those issuable upon exchange of Group LP partnership units) that are held by the existing Group LP Class A partnership unitholders (including our Managing Directors) will be eligible for resale from time to time, subject to certain contractual restrictions and to restrictions under the Securities Act of 1933, as amended (the "Securities Act").

        Certain Class A partnership unitholders in Group LP and holders of our Class A common stock are parties to agreements with us pursuant to which we have granted them registration rights. Under those agreements, after the expiration of the 180-day lock-up period, these persons will have the ability to cause us to register the shares of our Class A common stock (including the shares they could acquire upon exchange of Class A partnership units in Group LP), subject to certain contractual restrictions. See "Organizational Structure—Registration Rights."

The market price of our Class A common stock may be volatile, which could cause the value of your investment to decline.

        Securities markets worldwide experience significant price and volume fluctuations. This market volatility, as well as general economic, market or political conditions, could reduce the market price of our Class A common stock in spite of our operating performance. In addition, our operating results could be below the expectations of public market analysts and investors, and in response, the market price of our Class A common stock could decrease significantly. You may be unable to resell your shares of our Class A common stock at or above the initial public offering price.

Anti-takeover provisions in our charter documents and Delaware law could delay or prevent a change in control.

        Our amended and restated certificate of incorporation and bylaws may delay or prevent a merger or acquisition that a stockholder may consider favorable by permitting our board of directors to issue one or more series of preferred stock, requiring advance notice for stockholder proposals and

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nominations and placing limitations on convening stockholder meetings. In addition, there will be no cumulative voting in the election of directors, and our amended and restated certificate of incorporation will provide that directors may be removed, with or without cause, only with the affirmative vote of at least 80% of the voting interest of stockholders entitled to vote; provided, however, that for so long as the Class B Condition is satisfied, directors may be removed, with or without cause, with the affirmative vote of a majority of the voting interest of stockholders entitled to vote. In addition, we are subject to provisions of the Delaware General Corporation Law that restrict certain business combinations with interested stockholders. These provisions may also discourage acquisition proposals or delay or prevent a change in control, which could harm our stock price. See "Description of Capital Stock."

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus contains forward-looking statements, which reflect our current views with respect to, among other things, our operations and financial performance. You can identify these forward-looking statements by the use of words such as "outlook," "believes," "expects," "potential," "continues," "may," "will," "should," "seeks," "approximately," "predicts," "intends," "plans," "estimates," "anticipates" or the negative version of these words or other comparable words. Such forward-looking statements are subject to various risks and uncertainties. Accordingly, there are or will be important factors that could cause actual outcomes or results to differ materially from those indicated in these statements. We believe these factors include, but are not limited to, those described under "Risk Factors." These factors should not be construed as exhaustive and should be read in conjunction with the other cautionary statements that are included in this prospectus. We undertake no obligation to publicly update or review any forward-looking statement, whether as a result of new information, future developments or otherwise.

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ORGANIZATIONAL STRUCTURE

Overview

        Prior to this offering we will effect a reorganization described below. Following the reorganization and this offering, Moelis & Company will be a holding company and its only assets will be its partnership interests in Group LP, its equity interest in the sole general partner of Group LP, Moelis & Company Group GP LLC, and its interests in its subsidiaries. Moelis & Company will operate and control all of the business and affairs of Group LP and its operating entity subsidiaries indirectly through its equity interest in Moelis & Company Group GP LLC.

        The diagram below depicts our organizational structure following this offering.

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        Immediately following this offering:

•

Moelis & Company will hold Class A partnership units in Group LP representing                % of the total number of Class A partnership units in Group LP (or                % if the underwriters exercise their option to purchase additional shares in full);



•

certain of our existing Class A partnership unitholders (including all of our Managing Directors (other than certain non-U.S. based Managing Directors) indirectly through Partner Holdings) will hold Class A partnership units in Group LP representing                % of the total number of Class A partnership units in Group LP (or                % if the underwriters exercise their option to purchase additional shares in full);



•

certain of our existing Group LP Class A unitholders (including certain non-U.S. based Managing Directors and employees) will, directly or indirectly, own approximately                % of the Class A common stock (or                % if the underwriters exercise their option to purchase additional shares in full);



•

public stockholders will own                % of the Class A common stock (or                % if the underwriters exercise their option to purchase additional shares in full); and



•

Partner Holdings will own all of our Class B common stock.

The Reorganization

        On January 9, 2014, in contemplation of our initial public offering, Moelis & Company was incorporated in Delaware. Moelis & Company has not engaged in any business or other activities except in connection with its incorporation and this offering and currently holds no assets and has no subsidiaries other than Moelis & Company Group GP LLC.

        Our business is presently owned by Moelis & Company Holdings LP, which we refer to in this prospectus as Old Holdings. In connection with the consummation of this offering, a reorganization of the existing businesses of Old Holdings will be effected pursuant to which the existing advisory business of Old Holdings will be transferred to Group LP. Old Holdings will retain its existing asset management business, which includes managers of direct lending funds, hedge funds, private equity funds and collateralized loan obligation funds. We refer to these transactions as the "reorganization."

        As part of the reorganization, Old Holdings will distribute to its existing partners, directly or indirectly, all of the Group LP Class A partnership units it holds. However, Old Holdings and Moelis & Company may, in lieu of Group LP Class A partnership units, issue an equivalent number of shares of Moelis & Company Class A common stock to an existing partner of Old Holdings based on various considerations, including the partner's place of residence and tax considerations. Old Holdings will not retain an interest in Group LP following the reorganization. We and Old Holdings will be party to certain agreements following the reorganization and this offering. See "Certain Relationships and Related Person Transactions—Agreements with Old Holdings."

        As a result of the reorganization, Moelis & Company will be a holding company and its only assets will be its partnership interests in Group LP and its equity interest in the sole general partner of Group LP, Moelis & Company Group GP LLC, and its interests in its subsidiaries. Through our control of the sole general partner of Group LP, we will operate and control all of the business and affairs of Group LP and its operating entity subsidiaries.

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The Offering and Related Transactions

        In connection with this offering:

•

Moelis & Company will issue                shares of Class A common stock offered hereby for net proceeds of $             million (based on the mid-point of the range set forth on the cover page of this prospectus) and Group LP will issue to Moelis & Company an equivalent number of Class A partnership units;



•

Moelis & Company will issue                shares of Class B common stock for $                million and Group LP will issue to Moelis & Company an equivalent number of Class B partnership units; and



•

Moelis & Company will grant registration rights pursuant to which (i) Moelis & Company will be required to use its reasonable best efforts to file a shelf registration statement within                  months of the consummation of this offering, providing for the exchange of Group LP Class A partnership units held by certain Group LP non-employee Class A partnership unitholders for an equivalent number of shares of its Class A common stock and the resale of such shares at any time and from time to time thereafter, subject to applicable rules and restrictions imposed by the Company; (ii) Moelis & Company will be required to use its reasonable best efforts to file a shelf registration statement within                months of the expiration of the lock-up period relating to our Managing Directors, providing for the exchange of Group LP Class A partnership units held by such Managing Directors for an equivalent number of shares of Moelis & Company Class A common stock and the resale of shares of Moelis & Company Class A common stock by our Managing Directors at any time and from time to time, subject to applicable restrictions imposed by Moelis & Company; (iii) certain Group LP Class A unitholders will have the ability to cause the Company to register the shares of its Class A common stock they could acquire upon exchange of their Group LP Class A partnership units, subject to certain contractual restrictions; and (iv) certain Group LP Class A unitholders will have the ability to cause the Company to register the shares of its Class A common stock they could acquire upon exchange of their Group LP Class A partnership units, subject to certain contractual restrictions, in any public underwritten offerings by the Company after the expiration or earlier termination (if any) of the lock-up agreements referred to above, subject to customary pro rata cutbacks.



•

We will enter into a tax receivable agreement with certain Group LP Class A unitholders who hold in excess of                % of the Group LP Class A partnership units immediately prior to this offering (see "—Tax Receivable Agreement").



•

Moelis & Company will amend and restate its certificate of incorporation to provide for, among other things, the issuance of its Class A and Class B common stock.

Amended and Restated Limited Partnership Agreement of Group LP

        We will operate our business through Group LP and its subsidiaries. The provisions governing the operations of Group LP and the rights and obligations of its partners are set forth in the amended and restated limited partnership agreement of Group LP, the material terms of which are described below. A form of the limited partnership agreement of Group LP is filed as an exhibit to the registration statement of which this prospectus forms a part.

Governance

        Through our control of the general partner of Group LP, we will have unilateral control (subject to the consent of Partner Holdings on various matters) over the affairs and decisions of Group LP. As such, we, through our officers and directors, will be responsible for all operational and administrative

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decisions of Group LP and the day-to-day management of Group LP's business. Furthermore, Moelis & Company Group GP LLC, Group LP's general partner, cannot be removed as the general partner without Moelis & Company's approval. No Group LP unitholders, in their capacity as such, will have any authority or right to control the management of Group LP or to bind it in connection with any matter. However, Partner Holdings will have the ability to exercise majority voting control over Moelis & Company by virtue of its ownership of all shares of Class B common stock. See "—Amendments" and "Risk Factors—Risks Related to Our Class A Common Stock and this Offering—Control by Mr. Moelis of the voting power in Moelis & Company may give rise to actual or perceived conflicts of interest."

Voting and Economic Rights

        Group LP will issue Class A partnership units to Moelis & Company and to the existing holders of Old Holdings units who are to become Group LP Class A unitholders. In addition, Group LP will issue Class B partnership units to Moelis & Company. The Group LP Class B partnership units will correspond with the economic rights of shares of Moelis & Company's Class B common stock. Group LP Class A unitholders will have no voting rights by virtue of their ownership of Group LP partnership units, except for the right to approve certain amendments to the limited partnership agreement of Group LP, certain changes to the capital accounts of the limited partners of Group LP and any conversion of Group LP to a corporation other than for purposes of a sale transaction. Following the consummation of this offering, Partner Holdings will hold all shares of Moelis & Company Class B common stock, enabling it to exercise majority voting control over Moelis & Company and, indirectly, over Group LP. See "Risk Factors—Risks Related to Our Class A Common Stock and this Offering—Control by Mr. Moelis of the voting power in Moelis & Company may give rise to actual or perceived conflicts of interest."

        Pursuant to the Group LP limited partnership agreement, we have the right to determine when distributions will be made to the partners of Group LP and the amount of any such distributions. If we authorize a distribution, such distribution will be made to the partners of Group LP (i) in the case of a tax distribution (as described below), to the holders of partnership units in proportion to the amount of taxable income of Group LP allocated to such holder and (ii) in the case of other distributions, pro rata in accordance with the percentages of their respective partnership units, except as required under applicable tax law.

        The holders of partnership units in Group LP, including Moelis & Company, will incur U.S. federal, state and local income taxes on their allocable share of any net taxable income of Group LP. Net profits and net losses of Group LP will generally be allocated to its partners pro rata in accordance with the percentages of their respective partnership units, except as required under applicable tax law. In accordance with the partnership agreement, we intend to use commercially reasonable efforts to cause Group LP to make cash distributions to the holders of partnership units of Group LP for purposes of funding their tax obligations in respect of the income of Group LP that is allocated to them. Generally, these tax distributions will be computed based on our estimate of the net taxable income of Group LP allocable to such holder of partnership units multiplied by an assumed tax rate equal to the highest effective marginal combined U.S. federal, state and local income tax rate prescribed for an individual or corporation (taking into account the nondeductibility of certain expenses and the character of our income).

Coordination of Moelis & Company and Group LP

        Following the consummation of this offering, at any time we issue a share of Class A common stock for cash, the net proceeds received by us will be promptly transferred to Group LP, and Group LP will issue to us one of its Group LP Class A partnership units. At any time we issue a share of Class A common stock pursuant to our proposed equity incentive plan we will contribute to

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Group LP all of the proceeds that we receive (if any), and Group LP will issue to us one of its Group LP Class A partnership units, having the same restrictions, if any, attached to the shares of Class A common stock issued under the proposed equity incentive plan. Conversely, if we redeem or repurchase any of our shares of Class A common stock, Group LP will, immediately prior to our redemption or repurchase, redeem or repurchase an equal number of Group LP Class A partnership units held by us, upon the same terms and for the same price, as the shares of Class A common stock are redeemed or repurchased. We can only redeem or repurchase shares of Class A common stock if Group LP first redeems or repurchases an equivalent amount of Group LP Class A partnership units that we hold.

        Under the terms of the Group LP limited partnership agreement, we may in the future cause Group LP to issue Group LP partnership units or other, newly created classes of Group LP securities to one or more investors having such rights, preferences and other terms as we determine, and in such amount as we may determine. In addition, we may in the future elect to compensate our employees by granting them, directly or indirectly, Group LP partnership units, whether or not subject to forfeiture, or profits interests or other securities. Any such issuance would have a dilutive effect on the economic interest we hold in Group LP. In addition, in connection with any future issuances of Group LP Class A partnership units, we will issue our shares of Class B common stock having, for so long as the Class B Condition is satisfied, ten votes per share on a            -for-            basis, which would have a dilutive effect on the voting power of our then current holders of shares of Class A common stock. The tax receivable agreement will cover any exchanges of Group LP Class A partnership units issued to the current parties to that agreement after the offering, and it is possible that new investors in the Group LP Class A partnership units after the offering may become parties to the tax receivable agreement as well.

        Pursuant to the Group LP limited partnership agreement, we will agree that we will not conduct any business other than the management and ownership of Group LP, its general partner, and its operating entity subsidiaries, or own any other assets (other than cash or cash equivalents to be used to satisfy liabilities or other assets held on a temporary basis).

Material Corporate Transactions

        In the event that Group LP proposes to engage in a material corporate transaction, including a merger, consolidation, dissolution or sale of substantially all of its assets, we, through Moelis & Company Group GP LLC, in its capacity as the sole general partner of Group LP, shall have the power and authority to approve such a transaction. In addition, in the event that we, through Moelis & Company Group GP LLC, in its capacity as the sole general partner of Group LP, determine that all (or any portion) of the partnership units of Group LP, should be sold to a third party purchaser, we will have the right to compel the holders of the partnership units of Group LP to sell all or the same portion of their partnership units of Group LP to this third party purchaser.

Exchange Rights

        Subject to the transfer and exchange restrictions set forth in the Group LP limited partnership agreement and described below and other restrictions, if any, imposed by us, holders of fully vested Group LP Class A partnership units (other than Moelis & Company) may exchange these units for shares of Class A common stock on a one-for-one basis, subject to customary conversion rate adjustments for stock splits, stock dividends and reclassifications. At any time a share of Class A common stock is redeemed, repurchased, acquired, cancelled or terminated by us, one Group LP Class A partnership unit registered in the name of Moelis & Company will automatically be cancelled by Group LP so that the number of Group LP Class A partnership units held by Moelis & Company at all times equals the number of shares of Class A common stock outstanding.

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        We have reserved for issuance                shares of Class A common stock in respect of the aggregate number of shares of Class A common stock expected to be issued over time upon the exchanges by Group LP Class A partnership unitholders, unless Moelis & Company exercises its option to pay cash in lieu of shares of Class A common stock for some or all of such exchanged Group LP Class A partnership units. The cash amount will be based on the market price of the shares of Class A common stock. We may in the future cause Group LP to issue additional Group LP Class A partnership units that would also be exchangeable for shares of Class A common stock.

        Group LP Class A partnership units and Moelis & Company Class A common stock held by our Managing Directors (including through Partner Holdings) are subject to lock-up agreements for four years from this offering. After this period, Group LP Class A partnership units held by a Managing Director will become exchangeable into Class A common stock or cash as described above and Moelis & Company Class A common stock held by a Managing Director will become transferrable, in each case in three equal installments on each of the fourth, fifth and sixth anniversary of this offering. If a Managing Director terminates his or her employment with the Company prior to the end of the lock-up period, the Company will be entitled to extend the lock-up period until up to the tenth anniversary of this offering. We may waive the transfer and exchange restrictions set forth in the Group LP limited partnership agreement, including in connection with a secondary offering of shares of our Class A common stock by our Managing Directors. In addition, these restrictions cease to apply upon the death or termination of employment by us due to disability of the applicable Managing Director with respect to such Managing Director's Group LP Class A partnership units.

Conversion of Class B Common Stock

        Following each exchange of Group LP Class A partnership units for shares of Class A common stock, the holders of shares of Class B common stock will be required to surrender to Moelis & Company a corresponding number of shares of Class B common stock for conversion into shares of Class A common stock at a conversion rate based on the subscription price for such shares of Class B common stock to the initial public offering price of the Class A common stock. Group LP will also convert an equivalent number of Class B partnership units held by Moelis & Company into Class A partnership units based on the same Class B to Class A common stock conversion rate.

Indemnification and Exculpation

        To the extent permitted by applicable law, Group LP will indemnify its general partner, its executive officers and agents from and against any losses, liabilities, damages, costs, expenses, fees or penalties incurred by any acts or omissions of these persons, provided that the acts or omissions of these indemnified persons are not the result of fraud, intentional misconduct or a violation of the implied contractual duty of good faith and fair dealing, or any lesser standard of conduct permitted under applicable law.

        Group LP's general partner and its executive officers and agents will not be liable to Group LP, its limited partners or their affiliates for damages incurred by any acts or omissions of these persons, provided that the acts or omissions of these exculpated persons are not the result of fraud, intentional misconduct or a violation of the implied contractual duty of good faith and fair dealing, or any lesser standard of conduct permitted under applicable law.

Dissolution

        Group LP may be dissolved only upon the occurrence of certain unlikely events specified in the Group LP limited partnership agreement.

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Restrictive Covenants of our Managing Directors

        Our Managing Directors are subject to forfeiting their interests in vested Group LP partnership units and Moelis & Company Class A common stock they hold as of the offering if they terminate their employment without good reason and compete with the Company within 12 months thereafter, except for a certain limited number of designated units and stock which were awarded to replace equity of a former employer forfeited upon joining.

        Our Managing Directors have agreed not to solicit our employees during the term of their employment and for 12 months thereafter.

Registration Rights

        In connection with the completion of this offering, Moelis & Company will grant registration rights pursuant to which:

•

Moelis & Company will be required to use its reasonable best efforts to file a shelf registration statement within                                    months of the consummation of this offering, providing for the exchange of Group LP Class A partnership units held by certain Group LP non-employee Class A unitholders for an equivalent number of shares of its Class A common stock and the resale of such shares at any time and from time to time thereafter, subject to applicable restrictions imposed by Moelis & Company;



•

Moelis & Company will be required to use its reasonable best efforts to file a shelf registration statement within                                    months of the expiration of the lock-up period relating to our Managing Directors described above, providing for the exchange of Group LP Class A partnership units held by such Managing Directors for an equivalent number of shares of Moelis & Company Class A common stock and the resale of shares of Moelis & Company Class A common stock by our Managing Directors at any time and from time to time, subject to applicable restrictions imposed by Moelis & Company;



•

certain Group LP Class A unitholders will have the ability to cause the Company to register the shares of its Class A common stock they could acquire upon exchange of their Group LP Class A partnership units, subject to certain contractual restrictions; and



•

certain Group LP Class A unitholders will have the ability to cause the Company to register the shares of its Class A common stock they could acquire upon exchange of their Group LP Class A partnership units, subject to certain contractual restrictions, in any public underwritten offerings by the Company after the expiration or earlier termination (if any) of an applicable lock-up agreement subject to customary pro rata cutbacks.

        All fees, costs and expenses of underwritten registrations will be borne by Moelis & Company, other than underwriting discounts and selling commissions, which will be borne by each stockholder selling its shares. Our registration obligations will be subject to certain restrictions on, among other things, the frequency of requested registrations, the number of shares to be registered and the duration of these rights.

        Effective January 1, 2012, we entered into a strategic alliance with Sumitomo Mitsui Banking Corporation ("SMBC") and its subsidiary, SMBC Nikko Securities Inc. ("Nikko"). Pursuant to the strategic alliance agreement, we granted SMBC the right, under certain circumstances and subject to certain restrictions, to require us to register under the Securities Act shares of our Class A common stock issuable upon exchange of their Class A partnership units. Such securities registered under any registration statement will be available for sale in the open market unless restrictions apply.

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Rights of Partner Holdings and Stockholders Agreement

        In connection with the completion of this offering, Moelis & Company will enter into a stockholders agreement with Partner Holdings pursuant to which, for so long as the Class B Condition is satisfied, Partner Holdings will have approval rights over the following transactions:

•

any incurrence of indebtedness (other than inter-company indebtedness) in excess of $                ;



•

any issuance by us of equity or equity-related securities (other than preferred stock) that would represent, after such issuance or upon conversion, exchange or exercise, as the case may be, at least            % of the total combined voting power of our outstanding shares of Class A and Class B common stock, with each share of Class B common stock being treated as having one vote (except in certain circumstances);



•

the issuance by us of preferred stock;



•

any debt or equity investment by us (including any commitment to invest) in an amount greater than $                ;



•

any entry by us into a new line of business that requires a principal investment in excess of $                ;



•

the adoption of stockholder rights plans;



•

the appointment or termination of Section 16 officers;



•

any amendments to Moelis & Company's amended and restated certificate of incorporation or bylaws;



•

any amendments to Group LP's limited partnership agreement;



•

renaming Moelis & Company;



•

the adoption of annual budgets and business plans;



•

distributions to stockholders (except in certain circumstances);



•

entry into any merger, consolidation, recapitalization, liquidation or sale of Moelis & Company or all or substantially all of its assets or certain similar transactions involving Moelis & Company or entering into any agreement providing therefor (except in certain circumstances);



•

voluntarily initiating any liquidation, dissolution or winding up of Moelis & Company or permitting the commencement of a proceeding for bankruptcy, insolvency, receivership or similar action with respect to Moelis & Company or any of its subsidiaries or controlled affiliates;



•

the entry into or amendment of certain material contracts;



•

the entry into related party transactions;



•

the initiation or settlement of material legal actions; and



•

changes to our taxable or fiscal year.

        The effect of the agreement is that Partner Holdings may maintain control over our significant corporate transactions even if it holds less than a majority of the combined total voting power of our shares of Class A and Class B common stock.

        Our board of directors will nominate individuals designated by Partner Holdings equal to a majority of the board of the directors, for so long as the Class B Condition is satisfied.

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        The "Class B Condition" is defined as Mr. Moelis satisfying all of the following conditions:

          (i)  he maintains directly or indirectly ownership of an aggregate of at least                shares of Class A common stock of Moelis & Company and Equivalent Class A Shares (as defined below), subject to customary adjustments, which will represent approximately one-third of his ownership immediately following this offering;

         (ii)  he maintains directly or indirectly beneficial ownership (as defined below) of at least five percent (5%) of the Class A common stock of Moelis & Company (calculated, without duplication, on the basis that all issued and outstanding Group LP Class A partnership units not held by Moelis & Company or its subsidiaries had been exchanged for shares of Class A common stock of Moelis & Company);

        (iii)  he has not been convicted of a criminal violation of a material U.S. federal or state securities law that constitutes a felony or a felony involving moral turpitude;

        (iv)  he is not deceased; and

         (v)  his employment agreement has not been terminated in accordance with its terms because of a breach of his covenant to devote his primary business time and effort to the business and affairs of the Company and its subsidiaries or because he suffered an "incapacity" (i.e., order of incompetence or of insanity or permanent physical incapacity).

        "Equivalent Class A Shares" means, on any date, the number of shares of Class A common stock represented by any shares, units, interests, options, warrants, evidence of indebtedness, stock awards or other securities or awards which by their terms are directly or indirectly convertible into, exchangeable for, exercisable for or pursuant to which the holder is entitled to receive shares of Class A common stock, whether immediately, only after the passage of time or only after the satisfaction of conditions and notwithstanding any right to pay cash in lieu of shares of Class A common stock.

        "Beneficial ownership" has the same meaning given to it in Section 13(d) under the Exchange Act and the rules thereunder, except that a person will be deemed to have "beneficial ownership" of all securities that person has the right to acquire, whether the right is exercisable immediately, only after the passage of time or only after the satisfaction of conditions and notwithstanding any right to pay cash in lieu of such securities.

        After the Class B Condition ceases to be satisfied, for so long as the Secondary Class B Condition is satisfied, Partner Holdings will have certain approval rights over the following transactions:

•

the appointment or termination of the Chief Executive Officer;



•

any amendments to Moelis & Company's amended and restated certificate of incorporation or bylaws that materially and adversely affect in a disproportionate manner the rights of Mr. Moelis; and



•

any amendments to Group LP's limited partnership agreement that materially and adversely affect in a disproportionate manner the rights of Mr. Moelis.

        After the Class B Condition ceases to be satisfied, for so long as the Secondary Class B Condition is satisfied, our board of directors will nominate individuals designated by Partner Holdings equal to one quarter of the board of directors.

        For so long as either the Class B Condition or the Secondary Class B Condition is satisfied, Partner Holdings will retain the right to remove any director previously designated by it.

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        The "Secondary Class B Condition" is defined as Mr. Moelis satisfying all of the following conditions:

•

he maintains directly or indirectly ownership of an aggregate of at least                 shares of Class A common stock of Moelis & Company and Equivalent Class A Shares, subject to customary adjustments, which will represent approximately one-sixth of his ownership immediately following the offering; and



•

conditions (ii)-(v) required under the Class B Condition.

Tax Receivable Agreement

        On the date of this offering, Moelis & Company will be treated for U.S. federal income tax purposes as having directly purchased Class A partnership units in Group LP from the existing unitholders. In the future, additional Group LP Class A partnership units may be exchanged for shares of Class A common stock. We expect that, as a result of both this initial purchase and these future exchanges of Group LP Class A partnership units for shares of Class A common stock, the tax basis of Group LP's assets attributable to our interests in Group LP will be increased. These increases in the tax basis of Group LP's assets attributable to our interests in Group LP would not have been available to us but for this initial purchase and future exchanges of Group LP Class A partnership units for shares of Class A common stock. Such increases in tax basis are likely to increase (for tax purposes) depreciation and amortization deductions and therefore reduce the amount of income tax we would otherwise be required to pay in the future. These increases in tax basis may also decrease gain (or increase loss) on future dispositions of certain capital assets to the extent the increased tax basis is allocated to those capital assets. The IRS may challenge all or part of these tax basis increases, and a court could sustain such a challenge.

        We intend to enter into a tax receivable agreement with our eligible Managing Directors that will provide for the payment by us to our eligible Managing Directors of 85% of the amount of cash savings, if any, in U.S. federal, state and local income tax or franchise tax that we actually realize as a result of (a) the increases in tax basis attributable to our Managing Directors and (b) tax benefits related to imputed interest deemed to be paid by us as a result of this tax receivable agreement. We expect to benefit from the remaining 15% of cash savings, if any, in income tax that we realize. For purposes of the tax receivable agreement, cash savings in income tax will be computed by comparing our actual income tax liability to the amount of such taxes that we would have been required to pay had there been no increase to the tax basis of the tangible and intangible assets of Group LP as a result of the exchanges and had we not entered into the tax receivable agreement. The term of the tax receivable agreement will commence upon consummation of this offering and will continue until all such tax benefits have been utilized or expired, unless we exercise our right to terminate the tax receivable agreement for an amount based on an agreed value of payments remaining to be made under the agreement.

        Although we are not aware of any issue that would cause the IRS to challenge a tax basis increase, our eligible Managing Directors will not reimburse us for any payments previously made under the tax receivable agreement. As a result, in certain circumstances we may make payments to the eligible Managing Directors generally under the tax receivable agreement in excess of our actual cash tax savings. While the actual amount and timing of any payments under this agreement will vary depending upon a number of factors, including the timing of exchanges, the price of shares of our Class A common stock at the time of the exchange, the extent to which such exchanges are taxable and the amount and timing of our income, we expect that, as a result of the size of the increases of the tangible and intangible assets of Group LP attributable to our interests in Group LP, during the expected term of the tax receivable agreement, the payments that we may make to our eligible Managing Directors could be substantial. Payments made under the tax receivable agreement are required to be made

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within 225 days of the filing of our tax returns. Because we generally expect to receive the tax savings prior to making the cash payments to the selling holders of Group LP partnership units, we do not expect the cash payments to have a material impact on our liquidity.

        In addition, the tax receivable agreement provides that, upon a merger, asset sale, or other form of business combination or certain other changes of control or if, at any time, we elect an early termination of the tax receivable agreement, our (or our successor's) obligations with respect to exchanged or acquired units (whether exchanged or acquired before or after such change of control or early termination) will be based on certain assumptions, including that we would have sufficient taxable income to fully utilize the deductions arising from the increased tax deductions and tax basis and other benefits related to entering into the tax receivable agreement, and, in the case of certain early termination elections, that any units that have not been exchanged are deemed exchanged for the market value of the Class A common stock at the time of termination. Consequently, it is possible, in these circumstances, that the actual cash tax savings realized by us may be significantly less than the corresponding tax receivable agreement payments.

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USE OF PROCEEDS

        Our net proceeds from this offering will be approximately $            (or approximately $            if the underwriters exercise their option to purchase additional shares in full) after deducting underwriting discounts and commissions and estimated offering expenses payable by us (assuming the Class A common stock is sold at $            per share, which is the mid-point of the estimated initial public offering price range set forth on the cover page of this prospectus).

        Moelis & Company will use approximately $            of the net proceeds from this offering to purchase            Class A partnership units directly from Group LP. Moelis & Company will use the remaining $            of net proceeds to make one-time payments of $            to the partners of Old Holdings who received, directly or indirectly, shares of Class A common stock in exchange for the Group LP Class A partnership units they would otherwise have received in connection with the reorganization. See "Organizational Structure—The Reorganization."

        Group LP will use approximately $            of the net proceeds it receives from this offering to make a one-time cash distribution of $            to the partners of Old Holdings who hold Group LP Class A partnership units as of the day prior to the closing of this offering. Group LP will use the remaining $            of the net proceeds that it receives for general corporate purposes.

        As a result of Moelis & Company's payments of approximately $            and Group LP's distribution of approximately $            , the partners of Old Holdings will each have received their pro rata portion of the aggregate amount paid and distributed, as applicable. If the underwriters exercise their option to purchase additional shares, Moelis & Company and Group LP will make additional payments and distributions, respectively.

        A $1.00 increase (decrease) in the assumed initial public offering price per share would increase (decrease) the estimated net proceeds to us by approximately $                    (or approximately $                    if the underwriters exercise their option to purchase additional shares of Class A common stock in full), assuming that the number of shares of Class A common stock sold by us, as set forth on the cover page of this prospectus, remains the same and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us. Similarly, each increase (decrease) of 100,000 shares in the number of shares of Class A common stock offered by us would increase (decrease) the net proceeds to us from this offering by approximately $                    , assuming that the assumed initial public offering price remains the same, and after deducting the underwriting discounts and commissions.

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DIVIDEND POLICY

        Following this offering and subject to applicable law, we intend to pay a quarterly cash dividend initially equal to $             per share of Class A common stock, commencing with the                    . Any declaration and payment of future dividends to holders of our Class A common stock will be at the discretion of our board of directors and will depend on many factors, including our financial condition, earnings, cash flows, capital requirements, level of indebtedness, statutory and contractual restrictions applicable to the payment of dividends and other considerations that our board of directors deems relevant.

        Holders of our Class B common stock will be entitled to receive dividends of the same type as any dividends payable on outstanding Class A common stock. Dividends on shares of Class B common stock will be calculated based on the applicable subscription amount such that the aggregate dividends payable with respect to Class B common stock will equal the dividends payable with respect to an equivalent dollar amount of Class A common stock. See "Description of Capital Stock—Class B Common Stock."

        Moelis & Company will be a holding company and its only asset will be its partnership interests in Group LP, its equity interest in the sole general partner of Group LP, Moelis & Company Group GP LLC, and its interests in its subsidiaries. Under Delaware law, dividends may be payable only out of surplus, which is calculated as our assets less our liabilities and our capital, or, if we have no surplus, out of our net profits for the fiscal year in which the dividend is declared and/or the preceding fiscal year. We intend to cause Group LP to make distributions to Moelis & Company in an amount sufficient to cover dividends, if any, declared by us. If Group LP makes such distributions, each other Group LP Class A unitholder will be entitled to receive equivalent distributions from Group LP on its units.

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CAPITALIZATION

        The following table sets forth our cash and cash equivalents and capitalization as of December 31, 2013, as follows:

•

on an actual basis; and



•

on an as adjusted basis to give effect to the issuance and sale of Class A common stock in this offering at an assumed initial public offering price of $            per share (the mid-point of the range on the cover of this prospectus), after deducting underwriting discounts and commissions and estimated offering expenses payable by us, and the application of such proceeds as described herein.

        You should read this table in conjunction with the sections entitled "Organizational Structure," "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our combined financial statements and related notes included elsewhere in this prospectus.

        A $1.00 increase (decrease) in the assumed initial public offering price of $            per share, would increase (decrease) the as adjusted amount of each of cash and cash equivalents, additional paid-in capital, total stockholders' equity and total capitalization by approximately $                     million, assuming that the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same and after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

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DILUTION

        If you invest in our Class A common stock, your interest will be diluted to the extent of the difference between the initial public offering price per share of our Class A common stock and the net tangible book value per share of our Class A common stock after this offering. Dilution results from the fact that the per share offering price of the Class A common stock is substantially in excess of the book value per share attributable to the existing equityholders.

        Our net tangible book value as of December 31, 2013 was approximately $             million, or $            per share of our Class A common stock. Net tangible book value represents the amount of total tangible assets less total liabilities and net tangible book value per share represents net tangible book value divided by the number of shares of Class A common stock outstanding, after assuming that all of the Class A partnership unitholders of Group LP exchanged their vested units for newly-issued shares of our Class A common stock on a one-for-one basis.

        After giving effect to the sale of                    shares of Class A common stock in this offering at an assumed initial public offering price of $            per share, the mid-point of the price range on the cover of this prospectus, our net tangible book value would have been $            million, or $            per share. This represents an immediate increase in net tangible book value (or a decrease in net tangible book deficit) of $            per share to existing equityholders and an immediate dilution in net tangible book value of $             per share to new investors.

        The following table illustrates this dilution on a per share basis assuming the underwriters do not exercise their option to purchase additional shares:

        The following table summarizes the total number of shares of Class A common stock purchased from us, the total cash consideration paid to us and the average price per share paid by the existing Class A partnership equityholders and by new investors purchasing shares in this offering, assuming that all of the Group LP Class A partnership unitholders exchanged their vested units for shares of our Class A common stock on a one-for-one basis:

        Of the                Class A partnership units held by Class A partnership unitholders of Group LP (other than Moelis & Company), immediately following this offering                will be fully vested and                will be unvested. If we had assumed that all of the Class A partnership unitholders exchanged their unvested units in addition to their vested units for newly issued shares of our Class A common stock, the dilution in net tangible book value per share to new investors would have been greater, and the average price per share paid by the existing equityholders would have been lower.

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UNAUDITED PRO FORMA FINANCIAL INFORMATION

        The following unaudited pro forma condensed combined financial statements have been derived by applying pro forma adjustments to our historical combined financial statements included elsewhere in this prospectus.

        The adjustments necessary to fairly present the unaudited pro forma condensed combined financial statements have been based on available information and assumptions that we believe are reasonable. The unaudited pro forma condensed combined statements of operations and financial condition are presented for illustrative purposes only and do not purport to represent our results of operations or financial position that would actually have occurred had the transactions referred to below been consummated on January 1, 2013 for the unaudited pro forma condensed combined statement of operations, as applicable, and on December 31, 2013 for the unaudited pro forma condensed combined statement of financial condition, or to project our results of operations or financial position for any future date or period. The adjustments are described in the notes to the unaudited pro forma condensed combined financial statements.

        The pro forma adjustments principally give effect to the following items:

•

The reorganization transactions, including a capitalization of Old Holdings in an amount equal to $              and a pre-offering distribution to the partners of Old Holdings of approximately $              ;



•

The purchase by Moelis & Company of Class A partnership units directly from Group LP with the proceeds of this offering and the related effects of the tax receivable agreements;



•

The anticipated one-time cash distribution by Group LP to the partners of Old Holdings of a portion of the proceeds arising from the sale of Class A partnership units to Moelis & Company;



•

In the case of the unaudited pro forma condensed combined statement of operations, a provision for corporate income taxes at an effective tax rate of      %, which assumes Moelis & Company is taxed as a C corporation at the highest statutory rates apportioned to each state, local, and/or foreign tax jurisdiction and is reflected net of U.S. federal tax benefit; and



•

The granting of restricted stock units ("RSUs") and shares of Class A common stock to employees of the Company at the time of this offering.

        The unaudited pro forma condensed combined financial information presented assumes no exercise by the underwriters of the option to purchase up to an additional                  shares of Class A common stock from us and that the shares of Class A common stock to be sold in this offering are sold at $              per share, which is the midpoint of the price range on the front cover of this prospectus.

        Following the offering, we will incur costs associated with being a U.S. publicly traded company. Such costs will include new or increased expenses for such items as insurance, directors' fees, accounting work, legal advice and compliance with applicable U.S. regulatory and stock exchange requirements, including costs associated with compliance with the Sarbanes-Oxley Act and periodic or current reporting obligations under the Exchange Act. No pro forma adjustments have been made to reflect such costs due to the fact that they currently are not objectively determinable.

        The unaudited pro forma condensed combined financial information is included for informational purposes only and does not purport to reflect our results of operations or financial condition that would have occurred had we operated as a public company during the periods presented. You should read this unaudited pro forma condensed combined financial information together with the other information contained in this prospectus, including "Organizational Structure," "Management's

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Discussion and Analysis of Financial Condition and Results of Operations" and our combined financial statements and the notes thereto.

(a)

Reflects compensation expense associated with        RSUs issued in connection with this offering. The RSUs vest on a graded vesting schedule over a five-year period and therefore compensation expense will be recognized over this five-year period. This adjustment does not reflect one-time compensation expense associated with the issuance of       fully vested shares of Class A common stock. This adjustment does not reflect compensation expense related to awards issued contemporaneously with this offering but relating to the Company's annual compensation process.

(b)

As a partnership, we are not subject to U.S. federal income taxes, but we are subject to tax in certain foreign and local jurisdictions. An adjustment has been made to increase our effective tax rate to      %, which assumes the Company is taxed as a C corporation including (at the highest statutory rates apportioned to each) state, local, and foreign taxes.

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(c)

Reflects an adjustment to record the        % noncontrolling interests that partners of Old Holdings (other than the Company) own in Group LP relating to their partnership units, assuming            shares of Class A common stock are outstanding after this offering and        partnership units are held by partners of Old Holdings.

(d)

Reflects net income attributable to common shareholders divided by weighted average Class A common stock outstanding.

        We have not included the impact of shares of Class B common stock because these shares are entitled to an insignificant economic participation.

        Class A partnership units may be exchanged for our Class A common stock on a one-for-one basis, subject to customary conversion rate adjustments for splits, unit distributions and reclassifications and compliance with applicable lock-up, vesting and transfer restrictions. If all Class A partnership units were to be exchanged for Class A common stock immediately following the reorganization, fully diluted Class A common stock outstanding would be              . In computing the dilutive effect, if any, that the aforementioned exchange would have on earnings per share, we consider that net income available to holders of Class A common stock would increase due to elimination of the noncontrolling interest in consolidated entities associated with the Group LP Class A partnership units (including any tax impact). For the year ended December 31, 2013, such exchange is not reflected in fully diluted earnings per share as the assumed exchange was anti-dilutive.

        We issued        unvested RSUs to employees in connection with this offering. Basic weighted average shares of Class A common stock outstanding are not impacted by the RSUs. Further, the RSUs are not reflected in diluted weighted average shares as the calculation is dependent upon the average stock price for the year, which is not determinable.

        We issued        fully vested shares of Class A common stock to employees in connection with this offering. Weighted average shares of Class A common stock outstanding are increased by the full        shares and are included in the denominator for both basic EPS and diluted EPS.

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SELECTED HISTORICAL FINANCIAL AND OTHER DATA

        The following selected financial and other data should be read together with "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the historical financial statements and related notes included elsewhere in this prospectus.

        We derived the selected historical financial data as of December 31, 2013 and 2012 and for the years ended December 31, 2013, 2012 and 2011 from our audited combined financial statements which are included elsewhere in this prospectus.

        We derived the selected historical financial data as of December 31, 2011 from our audited combined financial statements which are not included in this prospectus.

        We derived the selected historical financial data as of December 31, 2010 and 2009 and for the years ended December 31, 2010 and 2009 from our unaudited combined financial statements which are not included in this prospectus. The unaudited combined financial statements for the years ended December 31, 2010 and 2009 have been prepared on substantially the same basis as the audited combined financial statements and include all normal and recurring adjustments that we consider necessary for a fair presentation of the financial position and operating results for these periods.