RISK FACTORS

         You should carefully consider the following risk factors in addition to the other information presented in this prospectus before investing in our ordinary shares. Any of the following risks could have a material adverse effect on our business, financial condition, results of operations or cash flow. If any of the following risks and uncertainties actually occurs, you may lose all or part of your original investment.

Business Risks

Our overall financial results are dependent on the ability of our Affiliates to generate earnings.

        OMAM is a holding company and is not a registered investment adviser under U.S. federal or state law. As such, OMAM does not manage investments for clients and does not directly receive management fees. All of OMAM's revenue generation is dependent on our Affiliates who are (or have subsidiaries who are) registered investment advisers under the Investment Advisers Act of 1940, as amended, or the Advisers Act, and receive the majority of their fees based on the market values of assets under management. Substantially all of OMAM's cash flows consist of distributions received from our Affiliates. As a result, OMAM's cash flows and ability to fund operations are largely dependent upon the profitability of our Affiliates.

        Each Affiliate is required to make certain cash distributions to us under the operating agreement we enter into with such Affiliate. Distributions to us from an Affiliate may be subject to the Affiliate maintaining sufficient working capital, regulatory requirements, claims of creditors of the Affiliate and applicable bankruptcy and insolvency laws. Any material decrease in profits at, or material reduction in distributions from, our Affiliates could negatively impact our business and results of operations.

The ability of our Affiliates to attract and retain assets under management and generate earnings is dependent on our Affiliates maintaining competitive investment performance, as well as market and other factors.

        Our financial performance is dependent upon the abilities of our Affiliates to minimize the risk of outflows through sound relative investment performance over measured periods of time compared to relevant benchmarks and peer performance results. The performance of our Affiliates' investment strategies, which can be impacted by factors within and/or outside the control of our Affiliates, including market and economic conditions, is critical to retaining existing client assets and investors in mutual funds our Affiliates sub-advise and attracting new client and investor assets. Poor performance can be caused by our Affiliates' choices in investing in sectors, industries, companies or assets that do not perform as well as others. Additionally, companies in which our Affiliates invest may incur negative changes in their financial conditions or suffer other adverse events that could reduce the values of the Affiliates' investments in those companies.

        Net flows related to our investment strategies can be affected by investment performance relative to other competing investment strategies or to established benchmarks. Investment management strategies are rated, ranked or assessed by independent third parties, distribution partners, and industry periodicals and services. These assessments often influence the investment decisions of our Affiliates' clients and investors in mutual funds our Affiliates sub-advise. If the performance or assessment of our investment strategies is seen as underperforming relative to peers, it could result in an increase in the withdrawal of assets by existing clients and investors in mutual funds our Affiliates sub-advise and the inability to attract additional investments from existing and new clients or investors. If a significant portion of clients or investors decide to withdraw their investments or terminate their investment management agreements, our Affiliates' abilities to generate earnings would decline and our results of operations and financial condition would be affected.

        In addition, assets could be withdrawn for any number of reasons other than poor absolute or relative investment performance, including macro-economic factors unrelated to investment

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performance, a reduction in market demand for the asset classes, products or strategies offered by our Affiliates, the loss of key personnel, price declines in the securities markets generally, price declines in those assets in which client assets are concentrated or changes in investment patterns of clients. Any of these factors could have a negative impact on the revenues and profits of an Affiliate and an adverse impact on our results of operations and financial condition.

Our relationships with our Affiliates are critical to our success.

        Maintaining strong relationships with our Affiliates is critical to our business model. Any potential disagreements over matters such as economics or management policies, growth strategies and compensation philosophy would impact our relationships with our Affiliates if not effectively managed. Furthermore, dissatisfaction by the management teams of our Affiliates with the services that we provide to them and the conditions upon which such services are provided also could result in a strained relationship with the management of that Affiliate. Any strains in the relationships that we have with our Affiliates could be detrimental to our overall business.

        Each of our Affiliates operates under ownership, governance and economic arrangements that we and such Affiliate negotiated either at inception or during the course of our relationship. Periodically, these arrangements are reviewed and, in some instances, may be renegotiated and revised. Any renegotiation that results in a reduction in our ownership interest in an Affiliate and/or a revision to the economic arrangements could reduce the economic benefits derived by us from that Affiliate.

We derive a substantial portion of our revenue from a limited number of Affiliates and investment strategies.

        As of June 30, 2014, Acadian Asset Management LLC, or Acadian, and Barrow, Hanley, Mewhinney & Strauss, LLC, or Barrow Hanley, represented approximately 78% of our assets under management, from which we derive a substantial portion of our revenue. An adverse change in the operating results of either of these Affiliates, whether as a result of poor investment performance, withdrawals of assets under management or otherwise, could have a substantial impact on our results of operations.

        While our Affiliates invest in a number of asset classes, a significant portion of our assets are invested in a limited number of investment strategies. As of June 30, 2014, approximately $116 billion, or 54%, of our assets under management were concentrated across five investment strategies: Barrow Hanley's large cap value equity (approximately $56 billion, or 26%) and mid cap value equity (approximately $8 billion, or 4%); Heitman LLC's real estate domestic private equity (approximately $17 billion, or 8%); and Acadian's emerging markets equity (approximately $21 billion, or 10%) and global equity (approximately $14 billion, or 7%). Consequently, our results of operations are dependent upon the abilities of our Affiliates that manage these investment strategies to minimize the risk of outflows through relatively strong performance over measured periods of time compared to relevant benchmarks and peer performance results. Also, certain investors may evaluate us on the basis of the asset-weighted performance of our assets under management. A relatively small change in the relative performance of one of our largest strategies, such as Barrow Hanley's large-cap value equity, could have a significant impact on the asset-weighted performance of our assets under management. Such volatility could adversely affect investors' perception of us.

Our business model limits our ability to manage our Affiliates' investment management practices and certain other aspects of their day-to-day operations.

        Our multi-boutique affiliate structure offers a diversity of investment styles and client bases. While our agreements with the majority of our Affiliates typically give us ultimate control over the business activities of those Affiliates, we generally do not become directly involved in managing their day-to-day operations, including investment management practices, policies and procedures, fee levels, marketing

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and product development, client relationships and employment and compensation programs. If we fail to intervene in potentially serious matters arising out of the day-to-day operations of our Affiliates, our reputation could be damaged and our results of operations adversely affected.

        For each of Heitman, LLC, or Heitman, and Investment Counselors of Maryland, LLC, or ICM, we exercise significant influence rather than control. Our ability to (i) direct the activities of these Affiliates, (ii) influence their decision-making processes and (iii) require our risk management and governance practices to be applied may be limited and not consistent with those of our controlled Affiliates.

Our growth strategy is dependent upon continued growth of our existing Affiliates and our ability to successfully acquire or invest in new Affiliates.

        Since we depend on distributions from our Affiliates to conduct our operations, the inability of our Affiliates to meet projected distribution levels could impact their ability to grow their businesses and contribute to our future growth at current or historical levels. In addition, capacity constraints, particularly on our Affiliates' smaller strategies, or the unavailability of appropriate investment opportunities could limit their ability to accept new client assets and, therefore, limit the growth of their and our revenue.

        Our growth strategy is also enhanced by our ability to successfully make new acquisitions or investments, which will depend on our ability to find suitable firms to acquire or invest in, our ability to negotiate agreements with such firms on acceptable terms, and our ability to raise the capital necessary to finance such transactions. Our most recent acquisition occurred in 2010. There is no certainty that we will identify suitable candidates at prices and terms we consider attractive, consummate any such acquisition or investment on acceptable terms, have sufficient resources to complete an identified acquisition or investment or that our strategy for pursuing acquisitions or investments will be effective. In addition, any acquisition or investment can involve a number of risks, including the existence of known liabilities or contingent liabilities or those not disclosed or known by us prior to closing an acquisition or investment. An acquisition or investment may impose additional demands on our staff that could strain our operational resources and increase the possibility of operational error, and require expenditure of substantial legal, investment banking and accounting fees. We may be required to issue ordinary shares or spend significant cash to consummate an acquisition or investment, resulting in dilution of ownership or additional debt leverage, or spend additional time and money on facilitating the acquisition or investment that otherwise would be spent on the development and expansion of our existing businesses. Following a completed acquisition or investment, failure by us and the target firm to achieve a strong, long-term relationship, or failure of the firm to realize incremental organic growth and growth through leveraging its relationship with us may result in our inability to achieve the anticipated benefits of the acquisition or investment, and could have an adverse impact on our business, financial condition and results of operations. In addition, the capital available for our use and the nature by which we deploy it is subject to the approval of our Parent in certain circumstances. Any future capital constraints imposed by our Parent may inhibit our ability to partner with new firms. See "Certain Relationships and Related Party Transactions—Relationship with Our Parent and OMGUK Following This Offering—Shareholder Agreement."

We and our Affiliates rely on certain key personnel, and our results are dependent upon our ability to retain and attract key personnel.

        We and our Affiliates depend on the skills and expertise of our key investment and management personnel, and our success and growth depends on our ability to attract and retain key personnel. Our Affiliates rely heavily upon the services of certain key investment and management personnel, many of whom have managed their firms for a number of years and who primarily guide the investment decision-making processes and strategies at the firms. The loss of key investment and management

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personnel at any of our Affiliates for any reason could have an adverse impact upon our business, results of operations and financial condition. Any of our key investment or management personnel could resign at any time, join a competitor or form a competing company. We have entered into non-competition agreements with some, but not all, of our investment and management personnel, but these agreements may not be enforceable or may not be enforceable to their full extent. In addition, we may agree to waive a non-competition agreement applicable to investment or management personnel in light of the circumstances of our relationship with that person.

        All of our Affiliates have established equity plans which are intended to attract, retain and motivate key personnel and pursuant to which key Affiliate personnel may be awarded or be able to purchase equity in their firm. The equity plans provide key employees with the opportunity to participate in the appreciation in the value of their businesses. Award documents under these plans typically limit a recipient's right to provide competitive services to clients of the Affiliates or solicit employees of the Affiliates for prescribed periods. Additionally, certain of our Affiliates' key executive management personnel may have entered into, or been offered the opportunity to enter into, agreements with us that are structured to motivate and retain such personnel. However, retention strategies we and our Affiliates have put into place may not be successful and, to the extent the plans do not produce the desired results, our Affiliates may suffer a loss of valued personnel.

        For certain of our Affiliates, a number of key management personnel are arriving at the point in their careers where they may be looking to limit their day-to-day involvement in their businesses or withdraw entirely. We have instituted succession planning at our Affiliates in an attempt to mitigate any disruption caused by these changes but cannot predict whether such efforts will be successful and whether the firms will be able to retain clients, assets and personnel or attract new assets and talent.

        We rely upon the contributions of our senior management team to establish and implement our strategy and to manage the future growth of our business. The amount and structure of compensation and opportunities for equity ownership we offer are key components of our ability to attract and retain qualified management personnel. In connection with our transition to a public company, we intend to make certain changes to our compensation structure, as described in "Compensation Discussion and Analysis—Compensation Plans Expected Post-Offering." There is no assurance that we will be successful in designing and implementing an attractive compensation model.

We and certain of our Affiliates face risks associated with investments in the real estate and timber markets.

        One of our Affiliates, Heitman, focuses on investments in private real estate equity, public real estate securities and real estate debt. Another of our Affiliates, Campbell Global, LLC, or Campbell Global, acquires and manages timberland for investors. As a result, we are exposed to the risks associated with investment in real estate and in timberland. Investment in real estate is subject to the risk of illiquidity of the investment, the possibility that cash generated from operations will not be sufficient to meet fixed obligations, changes in economic conditions affecting real estate ownership directly or the demand for real estate, the need for unanticipated expenditures in connection with environmental matters, changes in tax rates and other operating expenses, adverse changes in law, governmental rules, and fiscal policies, acts of God, environmental and waste hazards and other factors that are beyond the control of our real estate investment Affiliate. Timberland investments are subject to physical risks and economic risks. Physical risks include natural disasters, fire, pest infestation, disease, animal damage, and theft. Economic risks include price risk, supply risk, regulatory risk, demand risk, and liquidity risk. If our Affiliates do not adequately manage the unique risks associated with investments in real estate and timberland, or if any event occurs that is out of the control of our Affiliates, then our results of operations and financial condition may be adversely impacted.

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Our Affiliates' business operations are complex, and a failure to properly perform operational tasks or maintain infrastructure could have an adverse effect on our revenues and income.

        In addition to providing investment management services, our Affiliates must have the necessary operational capabilities to manage their businesses effectively in accordance with client expectations and applicable law. The required non-investment management functions include sales, marketing, portfolio recordkeeping and accounting, security pricing, trading activity, investor reporting, corporate governance, compliance, net asset value computations, account reconciliations and calculations of required distributions to accounts. Some of these functions are performed either independently or with the support of or in conjunction with us or third-party service providers that are overseen by our Affiliates. Also, certain of our Affiliates are highly dependent on specially developed proprietary systems. Any material failure to properly perform and monitor these non-investment management functions and operations, or adequately oversee the entities that provide the services, could result in potential liability to clients, regulatory sanctions, investment losses, loss of clients and reputational damage.

Reputational harm could result in a loss of assets under management and revenues for our Affiliates and us.

        The integrity of our brand and reputation, as well as the integrity of the brand and reputation of each of our Affiliates, is critical to the ability of us and our Affiliates to attract and retain clients, business partners and employees and maintain relationships with consultants. We operate within the highly regulated financial services industry and various potential scenarios could result in harm to our reputation. They include internal operational failures, failure to follow investment or legal guidelines in the management of accounts, intentional or unintentional misrepresentation of our Affiliates' products and services in offering or advertising materials, public relations information, social media or other external communications, employee misconduct or investments in businesses or industries that are controversial to certain special interest groups. The negative publicity associated with any of these factors could harm our reputation and those of our Affiliates and adversely impact relationships with existing and potential clients, third-party distributors, consultants and other business partners and subject us to regulatory sanctions. Damage to our brands or reputations would negatively impact our standing in the industry and result in loss of business in both the short term and the long term.

        Our brand and reputation are also tied to the brand and reputation of our Parent and those of our Parent's other subsidiaries. Immediately following this offering and, after giving effect to the transactions described herein, our Parent will indirectly own approximately        % of our outstanding ordinary shares, or    % if the underwriters exercise their over-allotment option in full. We exercise no control over the activities of our Parent or its affiliates. We may be subject to reputational harm, or our relationships with existing and potential clients, third-party distributors, consultants and other business partners could be harmed, if our Parent or any of its affiliates, previously, or in the future, among other things, engages in poor business practices, experiences adverse results, becomes subject to litigation or otherwise damages its reputation or business prospects. Any of these events might in turn adversely affect our own reputation, our revenues and our business prospects.

We or our Affiliates may not always successfully manage actual or potential conflicts of interests that may arise in our businesses.

        As we continue to expand the scope of our business, we increasingly confront actual, potential and perceived conflicts of interest relating to our activities and the investment activities of our Affiliates. Conflicts may arise with respect to decisions by our Affiliates regarding the allocation of specific investment opportunities among accounts in which Affiliates may receive an allocation of profits and accounts in which they do not or among client accounts that have overlapping investment objectives yet different fee structures.

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        Certain client accounts of our Affiliates have similar investment objectives and may engage in transactions in the same types of securities and instruments. These transactions could impact the prices and availability of the securities and instruments in which a client account invests and could have an adverse impact on an account's performance. An Affiliate may also buy or sell positions in a client account while that or another Affiliate, on behalf of other client accounts, is undertaking a similar, differing or opposite strategy, which could disadvantage the other accounts.

        The SEC and other regulators have increased their scrutiny of conflicts of interest. Our Affiliates have implemented procedures and controls to be followed when actual, potential or perceived conflicts of interest are identified, but it is possible that the procedures adopted by our Affiliates may not be effective in identifying or mitigating all conflicts which could give rise to the dissatisfaction of, or litigation by, investors or regulatory enforcement actions. Appropriately dealing with conflicts of interest is complex and difficult, and the reputations of us and our Affiliates could be damaged if we or they fail, or appear to fail, to deal appropriately with one or more potential or actual conflicts of interest. Regulatory scrutiny, litigation or reputational risk incurred in connection with conflicts of interest would adversely impact our business in a number of ways, including by making counterparties reluctant to do business with us, impeding our ability to retain or increase our assets under management, subjecting us to potential litigation and adversely impacting our results of operations.

        Conflicts of interest also may arise between our Affiliates where, for example, for competitive business reasons, more than one Affiliate may seek the same business opportunity, clients or talent or make other competitive business decisions.

        We may make business decisions which we believe are in the best interests of our Company but that may have indirect negative effects on one or more of our Affiliates. We also may be required to make strategic and financial or other resource allocation decisions that may directly benefit one or more Affiliates and not others. Any decision that does not directly or indirectly benefit an Affiliate could negatively impact our relationship with that Affiliate.

        Equity ownership by key employees of each Affiliate is at the level of the applicable Affiliate and not at the holding company level, although employees of our Affiliates may acquire our ordinary shares. Therefore, there may be instances where the interests of an Affiliate and its key employee equity-holders may not align with ours in effecting a desired outcome.

        While we endeavor to assess and resolve any conflicts in a manner that is not disruptive or detrimental to us, our Affiliates, or our Parent, there is no assurance that a resolution may be possible or the interests of all parties can be taken into account.

Impairment of our Affiliates' relationships with clients and/or consultants may negatively impact their businesses and our operating results.

        Our Affiliates have strong client and consultant relationships in their core institutional marketplaces, and they depend upon these relationships to successfully market their existing products and strategies and to introduce new products and strategies. Some Affiliates may have client exposures that are meaningful to their individual businesses. As of June 30, 2014, our Affiliates' top five client relationships represented 17% of total run rate ENI management fee revenue, including equity-accounted Affiliates, and our Affiliates' top 25 clients represented 35% of run rate ENI management fee revenue, including equity-accounted Affiliates. Total run rate ENI management fee revenue reflects the sum for each account at each of our seven Affiliates, of the product of (a) assets under management in each account at June 30, 2014, multiplied by (b) the relevant management fee rate on that account. This calculation includes the management fees paid by consolidated Funds, as well as all accounts at each of our equity-accounted Affiliates. Any negative changes in these relationships that reduce the number of client or consultant contacts, restrict access to existing or potential clients, or

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result in negative statements by a consultant, could have an adverse impact on our Affiliates' businesses and negatively impact our operating results.

The business of our Affiliates is dependent upon investment advisory agreements that are subject to negotiation, non-renewal, or termination, including termination upon assignment.

        Our Affiliates derive substantially all of their revenues from the fees charged to their clients under their investment advisory agreements with those clients. The agreements generally provide for fees to be paid on the basis of the market values of assets under management, although a portion also provide for fees to be paid on the basis of investment performance against stated benchmarks.

        An investment advisory agreement may be terminated by a client without penalty upon relatively short notice (typically no more than 30 days). In addition, the investment advisory agreements with registered investment companies generally may be terminated by the mutual fund or, in those instances where an Affiliate serves as a sub-adviser, the mutual fund's adviser, without penalty, upon 60 days' notice and are subject to annual approval by the mutual fund's board of directors or trustees. Clients may decide to terminate or not renew an agreement for poor investment performance or any variety of reasons beyond the control of our Affiliates. A decrease in revenues resulting from termination of an advisory agreement for any reason could have a material adverse effect on the revenue and profits of our Affiliates and a negative effect on our results of operations.

        Pursuant to the Advisers Act, investment advisory agreements between our Affiliates, who are (or who have subsidiaries who are) U.S. registered investment advisers, and their clients are not assignable without the consent of the client. As required by the Investment Company Act of 1940, or the Investment Company Act, investment advisory agreements between our Affiliates and investment company clients terminate upon their assignment. Assignment, as generally defined, includes direct assignments as well as assignments that may be deemed to occur, under certain circumstances, upon the direct or indirect transfer of a "controlling block" of the voting securities of the respective Affiliate. A transaction is not an assignment under the Advisers Act or the Investment Company Act, however, if it does not result in a change of actual control or management of the relevant Affiliate.

        It is not expected that this offering will constitute an assignment of any investment advisory agreements for purposes of the Advisers Act or the Investment Company Act, as applicable. However, our Parent could decide to sell a controlling block of our voting securities in the future, in which event the contractual anti-assignment and termination provisions of the investment advisory agreements between our Affiliates and their clients may be implicated. If an assignment of an investment advisory agreement is deemed to occur, and clients do not consent to the assignment or enter into a new agreement, our results of operations could be materially and adversely affected.

The historical returns of our existing investment strategies may not be indicative of their future results or of the investment strategies we may develop in the future.

        We have presented information with respect to the historical returns of our existing investment strategies throughout this prospectus, including under "Business—Products and Investment Performance". The historical returns of our Affiliates' strategies and the ratings and rankings our Affiliates or their strategies have received in the past should not be considered indicative of the future results of these strategies or of any other strategies that our Affiliates may develop in the future. The investment performance our Affiliates achieve for their clients varies over time and the variance can be wide. The ratings and rankings our Affiliates or their strategies have received are typically revised monthly. The historical performance and ratings and rankings presented herein are as of June 30, 2014 and for periods then ended unless otherwise indicated. The returns on the strategies of our Affiliates' have benefited during some periods from investment opportunities and positive economic and market conditions. In other periods, general economic and market conditions have negatively affected

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investment opportunities and the returns on our Affiliates' strategies. These negative conditions may occur again, and in the future our Affiliates may not be able to identify and invest in profitable investment opportunities within their current or future strategies.

Pressure on fee levels of our Affiliates and changes to their mix of assets could impact our results of operations.

        Our profit margins and net income are dependent on the ability of our Affiliates to maintain current fee levels for the products and services they offer. The competitive nature of the asset management industry has led to a trend toward lower fees in certain segments of the asset management market, and there can be no assurance that our Affiliates will be able to maintain their current pricing structures. Our Affiliates also may be required to restructure their fees due to regulatory changes. These factors also could inhibit the ability of our Affiliates to increase fees for certain products. A reduction in the fees charged by our Affiliates, or limited opportunities to increase fees, will reduce or limit our revenues and could reduce or limit our net income.

        The fees charged by our Affiliates on their assets under management vary by asset class and produce different revenues per dollar of assets under management based on factors such as the type of assets being managed, the applicable investment strategy, the type of client and the client fee schedule. Institutional clients may have significant negotiating leverage in establishing the terms of an advisory relationship, particularly with respect to the level of fees paid, and the competitive pressure to attract and retain institutional clients may impact the level of fee income earned by an Affiliate. In order for an Affiliate to maintain its fee structure in a competitive environment, it may elect to decline to manage additional assets from potential clients who demand lower fees even though our revenues may be adversely affected in the short term.

        Furthermore a shift in the mix of assets under management from assets that generate higher fees to those that generate lower fees may result in a decrease in revenues while aggregate assets under management remain unchanged or increase. Such shifts can occur as various investment strategies go in and out of favor due to competition in the industry or as a result of movements between asset classes or certain products no longer being available to investors. A decrease in revenues without a reduction in expenses will result in reduced net income.

        Changes in how clients choose to access asset management services may also exert downward pressure on fees. Some investment consultants, for example, are implementing programs in which the consultant provides a range of services, including selection, in a fiduciary capacity, of asset managers to serve as sub-adviser at lower fee rates than the manager's otherwise applicable rates, with the expectation of a larger amount of assets under management through that consultant. The expansion of those and similar programs could, over time, make it more difficult for us to maintain our fee rates.

Failure by our Affiliates to comply with investment guidelines set by their clients, including the boards of mutual funds that they sub-advise, or limitations imposed by applicable law could result in a loss of assets, potential damage awards or regulatory sanctions, which could adversely impact our results of operations or financial condition.

        As investment advisers, our Affiliates (or their registered subsidiaries) have fiduciary duties to their clients. Our Affiliates are required to follow specified investment guidelines established by their clients in the management of client accounts. Our Affiliates that sub-advise registered investment companies are also required to invest fund assets in accordance with guidelines contained in the Investment Company Act and applicable provisions of the Internal Revenue Code of 1986, as amended, or the Code, as well as any guidelines established by the boards of the investment companies. Affiliates that manage accounts subject to the fiduciary responsibility provisions of the Employee Retirement Income Security Act of 1974, as amended, or ERISA, must comply with the requirements of ERISA and

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regulations of the Department of Labor in their management of those plan accounts. An Affiliate's failure to comply with applicable client and regulatory guidelines could result in losses to a client which, depending on the circumstances, could result in an Affiliate obligation to make the client whole for such losses. If an Affiliate believed that the circumstances did not justify a reimbursement, or a client believed the reimbursement offered was insufficient, the client could seek to recover damages from the Affiliate, withdraw assets from management by the Affiliate or terminate its investment advisory agreement with the Affiliate. An Affiliate that fails to follow investment guidelines or other limitations in the management of a client account may be subject to actual and threatened lawsuits, or be subject to investigations and proceedings by governmental and self-regulatory organizations and potential damages, fines or sanctions. Any of these events could harm the reputations of us and our Affiliates and adversely impact our and their results of operations and financial condition.

If our techniques for managing risk are ineffective, we may be exposed to material unanticipated losses.

        In order to manage the significant risks inherent in our business, we must maintain effective policies, procedures and systems that enable us to identify, monitor and control our exposure to operational, legal and reputational risks. Our risk management methods may prove to be ineffective due to their design or implementation, or as a result of the lack of adequate, accurate or timely information or otherwise. If our risk management efforts are ineffective, we could suffer losses that could have a material adverse effect on our financial condition or results of operations. The potential for some types of operational risks, including, for example, trading errors, may be increased in periods of increased volatility, which can magnify the cost of an error. Although we have not suffered operational errors, including trading errors, of significant magnitude in the past, we may experience such errors in the future, which could be significant and the losses related to which we could be required to absorb. Additionally, we could be subject to litigation, particularly from our clients, and sanctions or fines from regulators. Our Affiliates' techniques for managing operational, legal and reputational risks in client portfolios may not fully mitigate the risk exposure in all economic or market environments, including exposure to risks that we might fail to identify or anticipate.

We or our Affiliates may be exposed to potential liability as a general partner or a controlling person.

        Our Affiliates are limited liability companies of which we are, or an entity controlled by us is, either the managing member or the majority member, except for ICM in which case we have certain consent and management rights. Certain of our Affiliates may serve as general partners, managing members or their equivalents for investment products that are organized as partnerships or other commingled vehicles. As such, we or an Affiliate may be exposed to liability to the limited liability company, partnership or investment vehicle or required to undertake certain obligations under applicable law that we or they otherwise would not be required to undertake as a holding company or investment adviser. In addition we may be deemed to be a control person of our Affiliates, as that term is defined in various United States federal and state statutes, and, as such, potentially liable for the acts of our Affiliates or their employees. Consequently, if under such circumstances any of our Affiliates incurs liabilities or expenses that exceed its ability to pay, we may be directly or indirectly liable for its payment to the extent provided in the governing documents of the limited liability company, partnership or investment vehicle or under applicable law. While we and our Affiliates maintain errors and omissions and general liability insurance in amounts believed to be adequate to cover certain potential liabilities, we cannot be certain that claims will not be made against us that exceed the limits of available insurance coverage, that the insurers will remain solvent and will meet their obligations to provide coverage or that an adequate amount of insurance coverage will continue to be available to us and our Affiliates at a reasonable cost. A judgment against any of our Affiliates and/or us in excess of available insurance coverage could have a material adverse impact on our business and financial condition.

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Our expenses are subject to fluctuations that could materially impact our results of operations.

        Our results of operations are dependent upon the level of our expenses and those of our Affiliates, which can vary from period to period. We and our Affiliates have certain fixed expenses that we incur as going concerns, and some of those expenses are not subject to adjustment. If our revenues decrease, without a corresponding decrease in expenses, our results of operations would be negatively impacted. While we and our Affiliates attempt to project expense levels in advance, there is no guarantee that an unforeseen expense will not arise or that we will be able to adjust our variable expenses quickly enough to match a declining asset base. Consequently, either event could have either a temporary or permanent negative impact on our results of operations.

The cost of insuring our business is meaningful and may increase.

        Our insurance costs are meaningful and can fluctuate significantly from year to year. In addition, certain insurance coverage may not be available or may only be available at prohibitive costs. As we renew our insurance coverage, we may be subject to additional costs caused by premium increases, higher deductibles, co-insurance liability, changes in the size of our business or nature of our operations, litigation or acquisitions or dispositions. We may also obtain additional forms of coverage resulting from our being a public company.

        We currently maintain certain insurance arrangements with our Parent and we benefit from the financial leverage our Parent brings to bear in negotiating certain insurance premiums with insurers specific to directors and officers insurance and excess errors and omission insurance. If we no longer were to be a member of our Parent's group of companies, we likely would lose the benefit of this arrangement and potentially be subject to less financially favorable insurance arrangements. Higher insurance costs and incurred deductibles, as with any expense, would reduce our net income. In addition, we may obtain additional liability insurance for our directors and officers. There have been historical periods in which directors' and officers' liability insurance and errors and omissions insurance have been available only with limited coverage amounts, less favorable terms or at prohibitive cost, and these conditions could recur.

Investments in non-U.S. markets and in securities of non-U.S. companies may involve foreign currency exchange risk, and tax, political, social and economic uncertainties, and a reduction in assets under management associated with investments in non-U.S. equities could have a disproportionate adverse impact on our results of operations.

        A significant amount of our Affiliates' assets under management is represented by strategies that primarily invest in securities of non-U.S. companies. Fluctuations in foreign currency exchange rates could negatively impact the account values and the investment returns of clients who are invested in these strategies, with a corresponding reduction in management fee income. In addition, an increase in the value of the U.S. dollar relative to non-U.S. currencies could result in a decrease in the U.S. dollar value of assets under management that are denominated in non-U.S. currencies, which in turn would result in lower revenues.

        Many non-U.S. financial markets are not as developed or as efficient as the U.S. financial markets and, as a result, have limited liquidity and greater price volatility and may lack established regulations. Liquidity in such markets also may be adversely impacted by political or economic events, government policies, expropriation, volume trading limits by foreign investors, and social or civil unrest. The ability to dispose of an investment and its market value may be adversely impacted by any of these factors. In addition, non-U.S. legal and regulatory financial accounting standards and practices may be different from those of the U.S., and there may be less publicly available information about non-U.S. companies and non-U.S. markets. Governments of foreign jurisdictions may assert their abilities to tax local gains and/or income of foreign investors, including clients of our Affiliates, which could adversely impact the

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economics associated with investing in foreign jurisdictions or non-U.S. based companies. These risks also could impact the performance of strategies that invest in such markets and, in particular, strategies that concentrate investments in emerging market companies and countries.

        In general, management fees for accounts that invest in non-U.S. equity markets, particularly emerging markets, are higher than those for accounts that invest in the domestic markets. Since approximately 38.5% of our Affiliates' total assets under management as of June 30, 2014 were invested in global, international and emerging markets equities, a significant reduction in assets under management associated with such investments could have a disproportionately adverse impact on our results of operations.

Our non-U.S. distribution initiatives may be unsuccessful, may expose us to other tax and regulatory risks and may not facilitate the growth of our business.

        One of the primary opportunities for growth lies in expanding the geographic regions in which our Affiliates' investment products and services are distributed. To assist our Affiliates in their non-U.S. distribution, we offer the assistance of our Company-led distribution team. The success of these non-U.S. initiatives is therefore dependent upon the ability of our and our Affiliates' teams to successfully partner in non-U.S. distribution efforts and to structure products that appeal to the global markets. The inability of the Company-led distribution team and our Affiliates to successfully execute on their non-U.S. distribution plans may adversely impact the growth prospects of our Affiliates.

        Our non-U.S. distribution initiative has required and will continue to require us to incur a number of up-front expenses, including those associated with obtaining regulatory approvals, as well as additional ongoing expenses, including those associated with the employment of additional support staff and regulatory compliance. Our employees routinely travel outside the United States in connection with our distribution efforts and may spend extended periods of time in one or more non-U.S. jurisdictions. Their activities outside the United States on our behalf may raise both tax and regulatory issues. If we are incorrect in our analysis of the applicability or the extent of the impact of non-U.S. tax or regulatory requirements, we could incur costs, penalties or be the subject of an enforcement or other action. We also expect that operating our business in non-U.S. markets generally will be more expensive than in the United States. To the extent that our revenues do not increase as much as our expenses in connection with our distribution initiatives outside the United States, our profitability could be adversely affected. Expanding our distribution initiatives into non-U.S. markets may also place significant demands on our existing infrastructure and employees.

Our outstanding indebtedness may impact our business and may restrict our growth and results of operations.

        Upon consummation of this offering, OMAM expects to have $175.0 million of debt outstanding under a revolving credit facility with third-party lenders as described in "Unaudited Pro Forma Consolidated Financial Data." For additional information regarding our new revolving credit facility, see "Management's Discussion and Analysis of Financial Condition and Results of Operations—Capital Resources and Liquidity—Future Capital Needs."

        We may incur additional indebtedness in the future for a variety of business reasons, including in relation to our acquisition strategy and in connection with our obligations under the deferred tax asset deed that we will enter into with OMGUK in connection with this offering (see "Certain Relationships and Related Party Transactions—Relationship with Our Parent and OMGUK Following This Offering—Deferred Tax Asset Deed"), and for seed or co-investment capital. We will be dependent on the cash flow generated from our Affiliates to service any indebtedness that is taken on by us.

        The level of our indebtedness has important consequences to investors in our ordinary shares. For example, our level of indebtedness may require us to use a substantial portion of our cash flow from operations to pay interest and principal on our debt, which would reduce the funds available to us for

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working capital, capital expenditures and other general corporate purposes and may limit our ability to pay future dividends. Too much debt may limit our ability to implement our business strategy; heighten our vulnerability to downturns in our business, the financial services industry or in the general economy and limit our flexibility in planning for, or reacting to, changes in our business and the financial services industry; or prevent us from taking advantage of business opportunities as they arise or successfully carrying out our plans to expand our business and our Affiliates' product offerings. Any of these consequences could have a material adverse effect on our financial condition or results of operations.

We may be unable to obtain sufficient capital and liquidity to meet the financing requirements of our business.

        Historically, we have relied principally upon our Parent to provide financing to facilitate the growth of our business and, in particular, to finance our acquisition strategy and investments in new products. In connection with the Reorganization, we intend to establish independent financing facilities with third-party lenders as described in "Management's Discussion and Analysis of Financial Condition and Results of Operations—Capital Resources and Liquidity—Future Capital Needs." Our future ability to incur debt may be restricted or limited by the regulations that govern our Parent's operations and our Parent's approval rights over our incurrence of indebtedness. We also may be subject to more onerous borrowing terms to the extent we do not have established relationships with third-party lenders. Borrowing from third-party lenders on less favorable terms could result in our having to allocate greater amounts of cash available in the future toward debt repayment and reduce cash available for other business opportunities. Our ability to finance our operations through borrowing from, and to repay maturing obligations to, our lenders will be dependent in large part on the profitability of our Affiliates and our future operating performance. Any future inability to obtain financing on reasonable terms and with reasonable restrictions on the operation of our business could impair our liquidity, have a negative impact on our growth and that of our Affiliates and negatively impact our financial condition.

Our business involves risks of potential litigation that could harm our business.

        We and our Affiliates may be named as defendants or co-defendants in lawsuits, or may be involved in disputes that include the threat of lawsuits seeking substantial damages. Any such legal action, whether threatened or actual, could result in reputational damage, loss of clients and assets, increased costs and expenses in resolving a claim, diversion of employee resources and resulting financial losses.

        Our Affiliates make investment decisions on behalf of their clients that could result in substantial losses to those clients. If their clients suffer significant losses or otherwise are dissatisfied with the service of one of our Affiliates, that Affiliate could be subject to the risk of legal liability or actions alleging negligent misconduct, breach of fiduciary duty, breach of contract, unjust enrichment and/or fraud. These risks often are difficult to assess or quantify and their existence and magnitude often remain unknown for substantial periods of time, even after an action has been commenced. Our Affiliates may incur substantial legal expenses in defending against litigation commenced by a client or regulatory authority. Substantial legal liability levied on any one of our Affiliates could have a material adverse effect on our business, financial condition, or results of operations and could cause significant reputational harm.

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Any significant limitation on the use of our facilities or the failure or security breach of our software applications or operating systems and networks, including the potential risk of cyber-attacks, could result in the disclosure of confidential client information, damage to our reputation, additional costs, regulatory penalties and financial losses.

        We and our Affiliates depend upon our principal business offices and our various centers of operation for the continued operations of our businesses. A disruption in the infrastructure that supports our businesses or prevents our employees from performing their job functions, including communication failures, natural disasters, terrorist attacks and international hostilities, may have a material impact on our ability to continue business operations without interruption. Insurance and other safeguards might not be available or might only partially reimburse us for our losses.

        Although we have back-up systems and disaster recovery programs in place and test their uses periodically, there can be no assurance that the recovery programs will be sufficient to mitigate any harm that may result from a disruption or disaster. Additionally, it is possible that any such disruption or disaster could have a significant impact on the general economy, domestic and local financial and capital markets or specific industries, including the financial services industry.

        A significant portion of our operations relies heavily on the secure processing, storage and transmission of confidential and other information as well as the monitoring of a large number of complex transactions. With the evolving proliferation of new technologies and the increasing use of the Internet and mobile devices to conduct financial transactions, financial institutions such as us have been, and will continue to be, subject to an increasing risk of cyber incidents from these activities. We and our Affiliates take protective measures to secure information, including through system security technology. However, our technology systems may still be vulnerable to unauthorized access, computer malware or other events that have a security impact, such as an authorized employee or vendor inadvertently causing the release of confidential information or third-party unauthorized access or account takeovers, which could materially damage our operations or cause the disclosure or modification of sensitive or confidential information. Breach of our technology systems through cyber-attacks, or failure to manage and secure our technology environment, could result in interruptions or malfunctions in the operations of our business, loss of valuable information, liability for stolen assets or information, remediation costs to repair damage caused by a breach, additional costs to mitigate against future incidents and litigation costs resulting from an incident. Moreover, loss of confidential client information could harm our reputation and subject us to liability under the laws that protect personal data, resulting in increased costs or loss of revenues.

        Our Affiliates and third parties with which we do business may also be sources of cybersecurity or other technological risks as we outsource certain functions. While we engage in certain actions to reduce the exposure resulting from outsourcing, such as performing onsite security control assessments, limiting third-party access to the least privileged level necessary to perform job functions, and restricting third-party processing to systems stored within our data centers, ongoing threats may result in unauthorized access, loss or destruction of data or other cyber incidents with increased costs and consequences to us such as those discussed above.

The carrying value of goodwill and other intangible assets on our balance sheet could become impaired, which would adversely affect our financial condition and results of operations.

        We have recorded goodwill and intangible asset impairments in the past and could incur such charges in the future as acquisitions occur and we take on more goodwill. We review the carrying value of goodwill and intangible assets not subject to amortization on an annual basis, or more frequently if indications exist suggesting that the fair value of our intangible assets may be below their carrying values. We test the values of intangible assets subject to amortization whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Should such review

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indicate impairment, a write-down of the carrying value of the intangible asset could occur, resulting in a non-cash charge that may, in turn, affect our reported results of operations, financial condition and shareholders' equity.

Claims for indemnification may be substantial and have a negative impact on our financial condition.

        We have engaged in a number of transactions involving the sale of businesses to third parties and to members of management of former Affiliates. As is customary in business transactions of these types, we were required to and did provide indemnifications with respect to third-party claims arising out of these transactions for limited periods of time with respect to certain claims, and for unlimited periods of time with respect to other claims. While we currently are not aware of exposure or potential exposure to any claim against us for indemnification, there can be no guarantee that a claim will not arise during the relevant indemnification period and that we will not have to provide the requisite indemnification. In addition, legal challenges to any potential claim for indemnification could result in increased legal expenses.

The failure of a counterparty to meet its obligations could affect our business adversely.

        Our Affiliates routinely execute transactions with counterparties in the financial industry and for the provision of services that are important to the business, and we may engage in transactions with counterparties as part of our corporate finance management function and for the provision of services. As a result, we and our Affiliates and clients have exposure to the credit, operational and other risks posed by such counterparties, including the risk of default by or bankruptcy of a counterparty. The failure of a counterparty to meet its obligations or provide the services we depend on for these or other reasons could adversely affect our ability to conduct our businesses and result in loss of client assets and potential liability.

We may be subject to financial criminal activity which could result in financial loss or damage to our reputation.

        Instances of financial criminal activity, personal trading violations and other abuses, including misappropriation of assets by internal or external perpetrators, may arise despite our internal control policies and procedures. Instances of such criminal activity by financial firms and their personnel, including those in the investment management industry, have led the U.S. government and regulators to increase enforcement of existing rules relating to such activities, adopt new rules and regulations and enhance oversight of the U.S. financial industry. As we expand our international operations, we will be subject to the rules of other jurisdictions that govern and control financial criminal activities and exposed to financial criminal activities on a more global scale. Compliance with existing and new rules and regulations may have the effect of increasing our expenses. Further, should any of our or our Affiliates' personnel be linked to financial criminal activity, either domestically or internationally, we would suffer material damage to our reputation which could result in a corresponding loss of clients and/or client assets and revenue.

        We and our Affiliates are vulnerable to reputational harm because we operate in an industry in which personal relationships, integrity and client confidences are of critical importance. For example, if an employee were to engage in illegal or suspicious activities, we or an Affiliate could be subject to legal or regulatory sanctions and suffer serious harm to our reputations (as a consequence of the negative perception resulting from such activities), and impairment to client relationships and the ability to attract new clients. Our Affiliates' businesses often require that they deal with confidential information. If their employees were to improperly use or disclose this information, even if inadvertently, our Affiliates and we could be subject to legal or regulatory action and suffer serious harm to our reputations and current and future business relationships.

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        It is not always possible to deter employee misconduct, and the precautions we take to detect and prevent this activity may not always be effective. In addition, the SEC has increased its scrutiny of the use of non-public information obtained from corporate insiders by professional investors. Employee misconduct, or even unsubstantiated allegations of misconduct, could adversely impact our reputation, current and future business relationships and our financial condition.

We are subject to the U.K. Bribery Act, the U.S. Foreign Corrupt Practices Act and other anti-corruption laws, as well as export control laws, customs laws, sanctions laws and other laws governing our operations. If we fail to comply with these laws, we could be subject to civil or criminal penalties, other remedial measures, and legal expenses, which could adversely affect our business, results of operations and financial condition.

        Our operations are subject to anti-corruption laws, including the U.K. Bribery Act 2010, or the Bribery Act, the U.S. Foreign Corrupt Practices Act, or the FCPA, and other anti-corruption laws that apply in countries where we do business. The Bribery Act, FCPA and these other laws generally prohibit us and our employees and intermediaries from bribing, being bribed or making other prohibited payments to government officials or other persons to obtain or retain business or gain some other business advantage. We and our commercial partners operate in a number of jurisdictions that may pose a risk of potential Bribery Act or FCPA violations, and we participate in collaborations and relationships with third parties whose actions could potentially subject us to liability under the Bribery Act, FCPA or local anti-corruption laws. In addition, we cannot predict the nature, scope or effect of future regulatory requirements to which our internal operations might be subject or the manner in which existing laws might be administered or interpreted.

        We are also subject to other laws and regulations governing our international operations, including regulations administered by the governments of the United Kingdom and the United States, and authorities in the European Union, including applicable export control regulations, economic sanctions on countries or persons, customs requirements and currency exchange regulations, or Trade Control Laws.

        There is no assurance that we will be completely effective in ensuring our compliance with all applicable anti-corruption laws, including the Bribery Act, the FCPA or other legal requirements, including Trade Control Laws. If we are not in compliance with the Bribery Act, the FCPA and other anti-corruption laws or Trade Control Laws, we may be subject to criminal and civil penalties, disgorgement and other sanctions and remedial measures, and legal expenses, which could have an adverse impact on our business, financial condition, results of operations and liquidity. Likewise, any investigation of any potential violations of the Bribery Act, the FCPA, other anti-corruption laws or Trade Control Laws by U.K., U.S. or other authorities could also have an adverse impact on our reputation, our business, results of operations and financial condition.

Industry Risks

We operate in a competitive environment.

        The investment management industry is highly competitive, with competition based on a variety of factors, including investment performance, investment management fee rates, continuity of investment professionals, and client relationships, the quality of services provided to clients, reputation and the strategies offered. We and our Affiliates compete against a broad range of domestic and international asset management firms, broker-dealers, hedge funds, investment banking firms and other financial institutions. We directly compete against these organizations with respect to investment products, distribution channels, opportunities to acquire other investment management firms and retention and recruitment of talent. The capital resources, scale, name recognition and geographic footprints of many of these organizations are greater than ours. The recent trend toward consolidation in the investment management industry, and the financial services industry in general, has served to increase the size and

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strength of a number of our competitors. Some investors may prefer to invest with an investment manager that is not publicly traded based on the perception that a publicly traded asset manager may focus on the manager's own growth to the detriment of investment performance for clients. Some competitors may operate in a different regulatory environment than we do, which may give them certain competitive advantages in the investment products and portfolio structures that they offer.

        In addition, each of our Affiliates competes against other investment managers offering the same or different investment strategies. The competition in our industry results in pressure on fees which may hinder the ability of our Affiliates to compete. All of our Affiliates rely upon their investment performance as a competitive advantage, which may not always position them to compare favorably to their competitors. In certain instances, our Affiliates also may compete against one another for clients. It is likely that new competitors will enter the market as there are low costs and limited barriers to entry.

        Our ability to attract assets also is dependent upon the ability of our Affiliates to offer a mix of products and services that meet client demand and their abilities to maintain investment management fees at competitive levels. There are a number of asset classes and product types that currently are not well covered by our Affiliates, such as index funds, passive ETFs and hedge funds. When these asset classes or products are in favor with either existing or potential clients, our Affiliates will miss the opportunity to attract and manage these assets and face the risk of assets being withdrawn in favor of competitors who manage the asset classes and/or provide these products. If our Affiliates are unable to compete effectively in their markets, our results of operations and potential business growth could be adversely affected.

        Our sole business is asset management. As a result, we may be more impacted by trends and issues, and more susceptible to negative events impacting the asset management industry than other more diversified financial services companies that provide asset management and other financial services.

We operate in a highly regulated industry, and continually changing federal, state, local and foreign laws and regulations could materially adversely affect our business, financial condition and results of operations.

        The investment management business is highly regulated and, as a result, our Affiliates are required to comply with a wide array of domestic and international laws and regulations. The requirements imposed by our regulators are designed to ensure the integrity of the financial markets and to protect customers and other third parties who deal with us, and are not designed to protect our shareholders. Accordingly, these regulators often serve to limit our activities, including through client protection and market conduct requirements.

        Our Affiliates are subject to extensive regulation in the U.S. through their primary regulator, the SEC, under the Advisers Act. Those of our Affiliates that act as investment advisers or sub-advisers to registered investment companies must comply with the terms of the Investment Company Act and the rules thereunder. The Advisers Act imposes numerous obligations on registered investment advisers, including fiduciary, record keeping, advertising and operational requirements, disclosure obligations, and prohibitions on fraudulent activities. The Investment Company Act regulates the structure and operations of registered investment companies and imposes additional obligations on advisers to registered investment companies, including detailed disclosure and regulatory requirements applicable to the registered investment companies and additional compliance responsibilities which must strictly be adhered to by the funds and their advisers. Certain of our advisory Affiliates also are subject to the rules and regulations adopted by the Commodity Futures Trading Commission, or the CFTC, under the Commodity Exchange Act, by the Department of Labor, under ERISA, the Financial Industry Regulatory Authority, Inc., or FINRA, and state regulators.

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        The domestic regulatory environment in which we operate has seen significantly increased regulation in recent years. In particular, the Dodd-Frank Act represents a comprehensive overhaul of the financial services industry in the U.S. and includes, among other things: (i) the creation of a Financial Stability Oversight Council to identify emerging systemic risks posed by financial firms, activities and practices, and to improve cooperation among federal agencies, (ii) the creation of the Consumer Financial Protection Bureau authorized to promulgate and enforce consumer protection regulations relating to financial products and services, and (iii) enhanced regulation of financial markets, including the derivatives and securitization markets. Certain provisions of the Dodd-Frank Act may require our Affiliates to change, or adopt new limitations on, the manner in which they conduct their business. The Dodd-Frank Act and the rules promulgated thereunder have also increased regulatory burdens and related reporting and compliance costs. Certain provisions may have unintended adverse consequences on the liquidity or structure of the financial markets. In addition, the scope and impact of many provisions of the Dodd-Frank Act remain to be determined by implementing regulations, some of which have involved lengthy proposal and promulgation periods and could lead to additional legislation or regulation. The Dodd-Frank Act impacts a broad range of market participants with whom our Affiliates interact or may interact. These changes may also impact the way in which our Affiliates conduct business with their counterparties and many aspects of the regulatory landscape continue to evolve. As a result of these uncertainties, the full impact of the Dodd-Frank Act on the investment management industry and on our and our Affiliates' businesses, in particular, cannot be predicted at this time.

        Developments in the current regulatory environment in the U.S. may include heightened and additional examinations and inspections by regulators. Regulators also may take a more aggressive posture on bringing enforcement proceedings resulting in fines, penalties and additional remedial activities.

        We and our Affiliates also are subject to the regulatory environments of the non-U.S. jurisdictions in which we and they operate, some of which also recently implemented or are in the process of implementing changes in regulations. In the United Kingdom we and our Affiliates are subject to regulation by two regulators, the Prudential Regulation Authority and the Financial Conduct Authority, which impose a comprehensive system of regulation on investment advisers and the manner in which we and they conduct our businesses. Some Affiliates are subject to and required to comply with the rules and regulations of the Irish Central Bank and the Luxembourg CSSF. We and our Affiliates are additionally subject to regulation relating to the offer and sale of financial products in each of the European Union countries in which we and they operate. The system of financial regulation in the European Union (including the U.K., Germany, Ireland, Luxembourg and Sweden) continues to develop and evolve and, as a result, the rules to which we and our Affiliates are subject (including rules relating to the remuneration of staff) are and will continue to be subject to change. Others that are registered in Australia, Canada, China, Hong Kong, Japan, South Korea, Russia, Singapore and the United Arab Emirates are subject to applicable regulations in those jurisdictions. As we execute on our growth strategy and continue to expand our distribution efforts into non-U.S. jurisdictions, including other member countries of the European Union, Latin America, the Middle East and certain other Asian countries, our Affiliates may be required to register with additional foreign regulatory authorities or otherwise comply with non-U.S. rules and regulations that currently are not applicable to our businesses and with respect to which we may have limited or no compliance experience. Our lack of experience in complying with any such non-U.S. or non-English laws and regulations may increase our risk of becoming a party to litigation or subject to regulatory actions.

        Our business, results of operations and financial condition may be adversely affected as a result of new or revised legislation or regulations or by changes in the interpretation or enforcement of existing laws and regulations in any of the jurisdictions in which we and our Affiliates conduct business. The ability of us and our Affiliates to function in this legislative and regulatory environment will depend on

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our and our Affiliates' abilities to monitor and promptly react to legislative and regulatory changes. It is impossible to determine the extent of the impact of any new laws, regulations or initiatives that may be proposed, or whether any of the proposals will become law. Any new laws or regulations could make compliance more difficult and expensive and affect the manner in which we and our Affiliates conduct business.

        Failure to comply with applicable laws or regulations could result in fines, suspension or revocation of an Affiliate's registration as an investment adviser, suspensions of individual employees, revocation of licenses to operate in certain jurisdictions or other sanctions, which could materially adversely affect our business, financial condition and results of operations. Even if an investigation or proceeding did not result in a fine or sanction, or the fine or sanction imposed against an Affiliate or us or our respective employees by a regulator were small in monetary amount, the adverse publicity relating to an investigation, proceeding or imposition of a fine or sanction could cause us to suffer financial loss, harm our reputation and cause us to lose business or fail to attract new business which would have a direct adverse impact on our business, financial condition and results of operations.

If we were deemed an investment company under the Investment Company Act, we would become subject to burdensome regulatory requirements and our business activities could be restricted.

        We do not believe that we are an "investment company" under the Investment Company Act. Generally, a company is an "investment company" if, absent an applicable exemption, it (i) is, or holds itself out as being, engaged primarily, or proposes to engage primarily, in the business of investing, reinvesting or trading in securities or (ii) engages, or proposes to engage, in the business of investing, reinvesting, owning, holding or trading in securities and owns or proposes to acquire "investment securities" having a value exceeding 40% of the value of its total assets (exclusive of U.S. government securities and cash items) on an unconsolidated basis. We believe we are primarily engaged in a non-investment company business and that less than 40% of our total assets (exclusive of U.S. government securities and cash items) on an unconsolidated basis are comprised of assets that could be considered investment securities.

        We and our Affiliates intend to conduct our operations so that we will not be deemed an investment company under the Investment Company Act. However, if we were to be deemed an investment company, restrictions imposed by the Investment Company Act, including limitations on our capital structure and our ability to transact with our Affiliates, could make it impractical for us to continue our business as currently conducted and could have a material adverse effect on our financial performance and operations.

Risks Related to Our Ownership Structure

Our Parent will continue to control us after this offering and will have significant power to control our business, affairs and policies.

        Upon completion of this offering, our Parent will beneficially own approximately    % of our outstanding ordinary shares, or     % if the underwriters exercise their over-allotment option in full. As a result of this ownership, and pursuant to the rights of our Parent under the Shareholder Agreement that we will enter into with our Parent prior to or concurrently with the consummation of this offering and policies and procedures adopted by our Board of Directors, our Parent will have significant power to control our business, affairs and policies, including the right to appoint a majority of the directors to our Board of Directors, and, accordingly, the appointment of management, the adoption of amendments to our articles of association and the number of ordinary shares available for issuance under our equity incentive plans for our prospective and existing employees. This concentration of ownership may have the effect of delaying or preventing a change in control of us or discouraging others from making tender offers for our ordinary shares, which could prevent shareholders from receiving a premium for their ordinary shares. It also may make it difficult for other shareholders to replace management and may adversely impact the trading price of our ordinary shares because investors often perceive disadvantages in owning ordinary shares in companies with controlling shareholders.

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        Pursuant to the Shareholder Agreement that we will enter into with our Parent, our Parent will, for so long as it remains the majority owner of our outstanding ordinary shares, have the right to appoint a majority of the directors to our Board of Directors and, for so long as it owns certain specified percentages of our outstanding ordinary shares that are less than a majority but greater than 7%, the right to appoint a certain number of directors to our Board of Directors. Our Board of Directors intends to adopt policies and procedures prior to the consummation of this offering, which will give our Parent significant control over certain matters, including budgets, business strategy, acquisitions, expenditures, financings, dividends, insurance and compensation, and will require us to comply with certain policies and procedures similar to those at our Parent.

        The ownership by our Parent of a significant majority of our ordinary shares upon completion of this offering, its right to appoint a majority of our directors and its significant control with respect to certain matters as described above will limit your ability to influence corporate matters. For information regarding the beneficial ownership of our outstanding ordinary shares by our Parent, see "Security Ownership of Certain Beneficial Owners and Management." For more information regarding our Shareholder Agreement with our Parent, see "Certain Relationships and Related Party Transactions—Relationship with Our Parent and OMGUK Following This Offering—Shareholder Agreement."

        In addition, pursuant to the Shareholder Agreement, our Parent will have approval rights over various matters until the date our Parent ceases to beneficially own more than 20% of our outstanding ordinary shares (provided that the consent rights related to the incurrence or guarantee of debt, the granting of liens and the declaration or payment of dividends shall not apply until the date that our Parent ceases to own more than 50% of our ordinary shares, so long as our Board of Directors approve such matters), including:

•

any merger or acquisition with consideration paid or payable (including a pro rata share of the debt assumed) of more than $100 million, or any disposition of assets with a fair market value of more than $100 million, involving us or one of our subsidiaries or controlled affiliates, on the one hand, and any other person, on the other hand;



•

any incurrence or guarantee of (or grant of a lien with respect to) external recourse debt in an amount greater than $300 million, plus the principal amount of the outstanding external debt on the date that our Parent ceases to beneficially own more than 50% of our outstanding ordinary shares;



•

any issuance of share capital other than (i) issuances of equity awards to directors or employees pursuant to a compensation plan or (ii) issuances of share capital in connection with an acquisition involving a consideration payable not exceeding $100 million;



•

entry into or amendment or termination of any material joint venture or strategic alliance;



•

any declaration or payment of a dividend other than in accordance with our dividend policy approved by our Board of Directors as of the date that our Parent ceases to beneficially own more than 50% of our outstanding ordinary shares;



•

listing or delisting of any securities on a securities exchange;



•

any agreement or arrangement that would conflict with the terms of the Shareholder Agreement;



•

any amendment, termination or waiver of any rights under our constitutional documents; and



•

any filing or petition under bankruptcy laws, admission of insolvency or similar actions by us or any of our subsidiaries or controlled affiliates, or our dissolution or winding-up.

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We will be a "controlled company" within the meaning of NYSE Listed Company Manual and, as a result, will qualify for, and intend to rely on, exemptions from certain corporate governance requirements.

        Upon the closing of this offering, our Parent will continue to beneficially own a majority of our ordinary shares. As a result, we will be a "controlled company" within the meaning of the NYSE Listed Company Manual. Under the NYSE Listed Company Manual, a company of which more than 50% of the voting power is held by an individual, group or another company is a "controlled company" and may elect not to comply with certain corporate governance requirements in the NYSE Listed Company Manual, including:

•

the requirement that a majority of our Board of Directors consist of independent directors;



•

the requirement that we have a nominating/corporate governance committee that is composed entirely of independent directors; and



•

the requirement that we have a compensation committee that is composed entirely of independent directors.

        Following this offering, we intend to utilize the exemptions to each of the requirements listed above. Accordingly, you will not have the same protections afforded to shareholders of companies that are subject to all of the NYSE corporate governance requirements of the NYSE Listed Company Manual. See "Management—Composition of our Board of Directors and Director Independence."

If our Parent sells a controlling interest in us to a third party in a private transaction, you may not realize any change-of-control premium on our ordinary shares and we may become subject to the control of a presently unknown third party.

        Following the completion of this offering, our Parent will beneficially own a substantial majority of our ordinary shares. Our Parent will have the ability, should it choose to do so, to sell some or all of our ordinary shares in a privately negotiated transaction, which, if sufficient in size, could result in a change of control of us. The ability of our Parent to privately sell such shares may not be subject to any requirement for a concurrent offer to be made to acquire all of our ordinary shares that will be publicly traded hereafter, which could prevent you from realizing any change-of-control premium on your ordinary shares that may otherwise accrue to our Parent upon its private sale of our ordinary shares. Additionally, if our Parent privately sells a significant equity interest in us, we may become subject to the control of a presently unknown third party. In addition, the rights of our Parent under the Shareholder Agreement may be assigned to any third party, but its rights to approve certain matters and to be informed of inquiries made or received by us regarding a potential change of control transaction may only be assigned to a transferee of a majority of our ordinary shares. Such third party may have interests that conflict with the interests of our other shareholders.

Our Parent's continuing significant interest in us following this offering may result in conflicts of interest.

        For as long as our Parent continues to beneficially own a significant amount of our outstanding ordinary shares, it will continue to be able to strongly influence or effectively control our decisions. See "Security Ownership of Certain Beneficial Owners and Management" and "—Our Parent will continue to control us after this offering and will have significant power to control our business, affairs and policies." Moreover, as long as our Parent continues to beneficially own more than 50% of our issued share capital, it will be able to determine the outcome of any corporate actions requiring approval of our shareholders by way of ordinary resolution (as such matters require approval by at least 50% of shareholders present and voting at the meeting at which the resolution is proposed). In addition, for so long as our Parent continues to beneficially own more than 75% of our issued share capital, it will be able to determine the outcome of any corporate actions requiring approval of our shareholders by way of special resolution, including any amendments to our constitutional documents (as such matters require approval by shareholders holding at least 75% of our issued share capital present and voting at the meeting at which the resolution is proposed).

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        Our Parent will also have the director appointment and approval rights described in "Certain Relationships and Related Party Transactions—Relationship with Our Parent and OMGUK Following This Offering—Shareholder Agreement." Because our Parent's interests may differ from those of other shareholders, actions our Parent takes or omits to take with respect to us, for as long as it is our controlling shareholder, including those corporate or business actions requiring its prior affirmative written consent or vote, may not be as favorable to other shareholders as they are to our Parent.

        The interests of our Parent could conflict in material respects with those of our other shareholders. For example, our Parent (through its control of our Board of Directors or pursuant to consent rights in the Shareholder Agreement) may prevent us from incurring indebtedness or making acquisitions with our own capital if such actions would adversely affect its capital ratios on a consolidated basis, negatively affect its credit rating or otherwise influence its financial metrics. Our Parent also could, for similar reasons, exert control over the amount and timing of our investments and dispositions, cause us to sell revenue-generating assets or control the issuance of additional ordinary shares. Any such actions by our Parent could affect the amount of cash available for distribution to shareholders. In addition, our Parent may from time to time acquire and hold interests in businesses that compete directly or indirectly with us. It also may pursue acquisition opportunities that may be complementary to our business and, as a result, those acquisition opportunities may not be available to us. Our Parent may have tax positions that are different from ours which could influence its decisions regarding whether and when to dispose of assets and whether and when to incur new or refinance existing indebtedness. In addition, the structuring of future transactions may take into consideration our Parent's tax considerations even where no similar benefit would accrue to us.

        Our Parent is also allowed to take into account the interests of parties other than us in resolving conflicts of interest. As an English plc our Parent owes no duty to our other shareholders. Furthermore, the Articles of Association specify that no officer or director owes any duty to any shareholder. Other affiliates of our Parent and existing and former personnel employed by our Parent may not be subject to non-competition, non-solicitation and confidentiality agreements to which members of our management and those of our Affiliates are subject and thus may not be prohibited from engaging in other businesses or activities, including those that might be in direct competition with us. Our Parent also may control the enforcement of obligations owed to us by it and its affiliates and decide whether to retain separate counsel or others to perform services for us.

        The Shareholder Agreement and our Board's approach to corporate governance and risk management, including policies which our Board of Directors intends to adopt prior to the consummation of this offering, which will give our Parent significant control over our business, may impose additional controls and information sharing by us and our Affiliates from that deemed to be standard in the investment management industry. While overlaying these additional governance and risk management structures onto the highly regulated investment management business may be viewed as a desirable added layer of regulatory oversight, it may be viewed by Affiliates and potential acquisition targets as being overly cumbersome, controlling and costly and thus a competitive deterrent to a third party becoming affiliated with us.

        Through participation in our Parent's incentive compensation plans, our executive officers, one of whom also serves as a director of our Company, have acquired shares or been granted restricted shares of our Parent, and they may continue to participate in such plans following this offering. As a result, their ownership of shares of our Parent may exceed their ownership or rights to acquire ordinary shares of our Company at the time of this offering and into the future, which may present a conflict of interest for the executive.

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Our ability to pay regular dividends to our shareholders is subject to the discretion of our Board of Directors and our Parent and may be limited by our holding company structure and applicable provisions of the laws of England and Wales.

        Following completion of this offering, we will initially target a dividend payout as described in "Dividend Policy." Beginning on the date our Parent ceases to own more than 50% of our ordinary shares and ending on the date that our Parent ceases to beneficially own at least 20% of our outstanding ordinary shares, the approval of our Parent will be required to declare any dividend other than in accordance with the dividend policy approved by our Board of Directors as of the date our Parent ceases to beneficially own more than 50% of our outstanding ordinary shares. In addition, with the approval of our Parent (for so long as required), our Board of Directors may change the amount or frequency of dividends or discontinue the payment of dividends entirely. In addition, as a holding company, we will be dependent upon the ability of our Affiliates to generate earnings and cash flows and distribute them to us so that we may pay dividends to our shareholders. The ability of our Affiliates to distribute cash to OMAM will be subject to their operating results, cash requirements and financial condition, the applicable provisions of governing law which may limit the amount of funds available for distribution, their compliance with covenants and financial ratios related to existing or future indebtedness, and their other agreements with third parties. As a consequence of these various limitations and restrictions, we may not be able to make, or may have to reduce or eliminate, the payment of dividends on our ordinary shares.

Some of our directors are executive officers of our Parent.

        All of our directors immediately following this offering will have been designated to our Board of Directors by our Parent. Three of these directors will be officers or employees of our Parent. Because of their positions as an officer or employee of our Parent, these three directors own substantial amounts of shares of our Parent. Ownership interests of these three directors in shares of our Parent, or service of certain of our directors as officers of our Parent, may create, or may create the appearance of, conflicts of interest when a director is faced with a decision that could have different implications for the two companies. These potential conflicts could arise, for example, over matters such as the desirability of an acquisition opportunity, employee retention or recruiting, capital management or our dividend policy and could result in our Company taking actions that are in the best interests of our Parent but not our other shareholders. Our Board of Directors has authorized any conflict of interest that any director appointed to our Board of Directors by our Parent from time to time may have with respect to any position held, or other interest, in any member of our Parent's group. Notwithstanding any such conflict, directors appointed to our Board of Directors by our Parent shall be entitled to receive all information provided to, and participate fully in all deliberations and participate in any vote of, our Board of Directors, for all matters.

Our separation from our Parent could have a negative impact on our business and results of operations due to our Parent's strong brand and reputation.

        We have benefitted from being a wholly-owned subsidiary of our Parent and a member of our Parent's group of companies as we believe the association has provided us with preferred status among a variety of service providers, vendors and others due to our Parent's globally recognized brand, perceived high quality products and services and strong capital base and financial strength. Immediately prior to the completion of this offering, we intend to enter into an intellectual property license agreement with OMUSH, our Parent and, solely for the intellectual property owned by it applicable to the agreement, Old Mutual Life Assurance Company (South Africa) Ltd., or OMLACSA, which we refer to as the Intellectual Property Agreement. Pursuant to the Intellectual Property Agreement, our Parent and OMLACSA will grant us a limited, non-exclusive, fully paid-up, royalty-free, non-transferable, non-sublicensable license to use certain trademarks, servicemarks, names and logos, including the names "Old Mutual", "OM" and the "OM 3 anchor design logo" with respect to our business and in connection with this offering, worldwide, subject to certain exceptions set forth in the

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Intellectual Property Agreement. The license term shall be for the period commencing on the date of the closing of this offering and ending six months after the date on which our Parent ceases to directly or indirectly own a majority of our outstanding ordinary shares; provided, however that under the Intellectual Property Agreement, our Parent and OMLACSA have given us a perpetual right (i) to use the name "OM Asset Management" as all or part of our corporate or trade names, (ii) to use "OMAM" in all or part of our corporate or trade names, businesses and activities, including in any advertising or promotional materials, and as a ticker symbol and (iii) to use omam.com as a website and an email address. After this license expires, we must cease using the licensed intellectual property (other than as described above and in the Intellectual Property Agreement) and any benefits that we derived from the use of the "Old Mutual" brand name and logo will likely be diminished or eliminated.

        In addition, certain of our Parent's other affiliates have established investment advisory and other investment-advisory related relationships with our Affiliates pursuant to which our Affiliates derive revenue. For the quarter ended June 30, 2014, our Parent and its subsidiaries (other than the Company and our Affiliates) contributed less than 2% of total ENI revenue including equity-accounted Affiliates. We cannot predict whether these relationships would continue when we are no longer a wholly-owned subsidiary of our Parent.

        This offering could adversely impact our relationships with certain of our current or potential business partners as we may no longer be viewed as a part of our Parent's group of companies. If we no longer are entitled to benefit from the relationship with our Parent as a result of this offering, we may not be able to obtain certain services at the same level or obtain the same benefit through new, independent relationships with third-party vendors. Likewise, we may not be able to replace the service and arrangement in a timely manner or on terms and conditions, including cost, as favorable as those we previously have received as a subsidiary of our Parent. Some third parties may re-price, modify or terminate their vendor relationships with us after we are no longer a wholly-owned subsidiary of our Parent.

        The risks relating to our separation from our Parent could materialize or evolve at any time, including immediately upon the completion of this offering, when our Parent's beneficial ownership in our ordinary shares will decrease to approximately      % (or approximately      % if the underwriters' over-allotment option to purchase additional shares is exercised in full), and at a later date if our Parent were to decide to decrease its ownership of our ordinary shares.

        We cannot accurately predict the impact that our separation from our Parent will have on our business and the businesses of our Affiliates, distribution partners, service providers, vendors and other business partners.

Risks Related to Our Tax Matters

The Internal Revenue Service, or the IRS, may not agree to treat OMAM as a foreign corporation for U.S. federal tax purposes.

        Although OMAM is incorporated in England and Wales, which are part of the United Kingdom, the IRS may assert that it should be treated as a U.S. corporation (and, therefore, a U.S. tax resident) for U.S. federal tax purposes pursuant to section 7874 of the Code. For U.S. federal tax purposes, a corporation generally is considered a tax resident in the jurisdiction of its organization or incorporation. Because OMAM is a United Kingdom incorporated entity, it would generally be classified as a foreign corporation (and, therefore, a non-U.S. tax resident) under these rules. Section 7874 of the Code provides an exception under which a foreign incorporated entity may, in certain circumstances, be treated as a U.S. corporation for U.S. federal tax purposes.

        For OMAM to be treated as a foreign corporation for U.S. federal tax purposes under section 7874 of the Code, immediately after the Reorganization, either (i) the former stockholders of OMUSH, i.e., OMGUK, must own (within the meaning of section 7874 of the Code) less than 80% (by both vote and value) of our ordinary shares by reason of holding shares in OMUSH immediately prior

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to the Reorganization, excluding for this purpose shares owned by the expanded affiliated group including OMAM, or (ii) OMAM must have substantial business activities in the United Kingdom (taking into account the activities of our expanded affiliated group).

        Based on the rules for determining share ownership under section 7874 of the Code, in particular the rule excluding shares owned by OMGUK, which should be treated as a member of the expanded affiliated group including OMAM, we believe that OMGUK should be treated as owning less than 80% of our ordinary shares after the Reorganization and that, therefore, OMAM should be treated as a foreign corporation for U.S. federal income tax purposes, although no assurances can be given in this regard. If OMAM were to be treated as a U.S. corporation, income it earned would become subject to U.S. taxation, and the gross amount of any dividend payments to its non-U.S. shareholders could be subject to 30% U.S. withholding tax, depending on the application of any income tax treaty that might apply to reduce the withholding tax.

        For further discussion of the application of section 7874 of the Code to the Reorganization, see "Material U.S. Federal Tax Considerations for Holders of Ordinary Shares—Tax Consequences of the Reorganization."

Future changes to the tax laws under which we should be treated as a foreign corporation for U.S. federal tax purposes and changes in other tax laws relating to multinational corporations could adversely affect us.

        Under current law, as noted above, OMAM should be treated as a foreign corporation for U.S. federal tax purposes. Changes to section 7874 of the Code or the U.S. Treasury regulations promulgated thereunder or future IRS guidance could affect OMAM's status as a foreign corporation for U.S. federal tax purposes, and any such changes or future IRS guidance could have prospective or retroactive application. In addition, recent legislative proposals have aimed to expand the scope of U.S. corporate tax residence. Such legislation, if passed, could also affect OMAM's status as a foreign corporation for U.S. federal tax purposes. Any of these changes to such laws or regulations, or future IRS guidance, could adversely affect us.

        Moreover, the U.S. Congress, government agencies in non-U.S. jurisdictions where we and our Affiliates do business, and the Organization for Economic Co-operation and Development have each recently focused on issues related to the taxation of multinational corporations. As a result, the tax laws in the U.S. and other countries in which we and our Affiliates do business could change on a prospective or retroactive basis, and any such changes could adversely affect us.

Section 7874 of the Code could limit OMUSH's ability to utilize its U.S. tax attributes to offset certain U.S. taxable income, if any, generated by certain specified transactions for a period of time following the Reorganization.

        Following the acquisition of a U.S. corporation by a foreign corporation, section 7874 of the Code can limit the ability of the acquired U.S. corporation and its U.S. affiliates to utilize U.S. tax attributes such as net operating losses to offset U.S. taxable income resulting from certain transactions.

        These limitations will apply if, immediately after the Reorganization, (i) the former stockholder of OMUSH, i.e., OMGUK, owns (within the meaning of section 7874 of the Code) at least 60% (by both vote and value) of our ordinary shares by reason of holding shares in OMUSH immediately prior to the Reorganization, excluding for this purpose shares owned by the expanded affiliated group including OMAM, and (ii) we do not have substantial business activities in the United Kingdom (taking into account the activities of our expanded affiliated group).

        Based on the rules for determining share ownership under section 7874 of the Code, in particular the rule excluding shares owned by OMGUK, which should be treated as a member of the expanded affiliated group including OMAM, we believe that OMGUK should be treated as owning less than 60% of our ordinary shares after the Reorganization, and that therefore, OMUSH should not be subject to the limitations described above, although no assurances can be offered in this regard. If such limitations

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were to apply, the U.S. consolidated group that includes OMUSH would owe potentially more U.S. tax due to the inability to utilize these tax attributes, but there would likely be a corresponding reduction in the obligation of OMAM to make payments under the deferred tax asset deed, in the same or subsequent periods. For further discussion of the deferred tax asset deed, see "Certain Relationships and Related Party Transactions—Relationship with Our Parent and OMGUK Following This Offering—Deferred Tax Asset Deed."

        For further discussion of the application of section 7874 of the Code to the Reorganization, see "Material U.S. Federal Tax Considerations for Holders of Ordinary Shares—Tax Consequences of the Reorganization."

Dividends and interest from OMUSH to OMAM, and dividends, interest or other income from foreign entities owned by Affiliates or investment in other foreign countries may be subject to withholding taxes.

        Under U.S. federal income tax law, dividends and other distributions from Affiliates of OMUSH to OMUSH and from OMUSH to OMAM UK Limited, or UK Sub, should not be subject to U.S. withholding tax. Additionally, dividends from OMAM US, Inc., or US Sub, to OMAM should not be subject to U.S. withholding tax under the income tax treaty between the United Kingdom and the United States, or the Treaty, provided that OMAM satisfies the minimum holding period requirements set forth in the Treaty. Under U.S. federal income tax law, interest paid by OMUSH to UK Sub should not be subject to U.S. withholding tax and, under the Treaty, interest paid by US Sub to OMAM should also not be subject to U.S. withholding tax. The IRS, however, may challenge any determination that OMAM is eligible for benefits under the Treaty, or may assert that OMAM does not qualify for a complete exemption from withholding tax on dividends under the Treaty. If OMAM is not eligible for benefits under the Treaty, the gross amounts of such dividends or interest would be subject to a 30% U.S. withholding tax. If OMAM qualifies for benefits under the Treaty, but not for a complete exemption from withholding tax on dividends, the gross amount of such dividends should nevertheless qualify for a reduced withholding tax rate of 5%.

        Under English law, dividends and other distributions from a U.K. corporation are not subject to U.K. withholding tax. However, dividends, interest or other income earned by OMUSH or Affiliates of OMUSH from foreign entities that OMUSH or such Affiliates control or have invested in may be subject to foreign withholding taxes. Unless our share of these withholding taxes is fully credited against our U.S. or U.K. income tax liability or fully refunded, it could increase our aggregate tax burden. Although we intend to arrange the ownership of our foreign subsidiaries, our intercompany dividends, interest and other payments and our investments in foreign countries on our own behalf and on behalf of our clients with a view to minimizing the incurrence of such withholding taxes, there can be no assurance that such arrangements will have the intended result.

If we were treated as a "controlled foreign corporation" for U.S. federal income tax purposes, U.S. holders of 10% or more of the voting power of our ordinary shares may be subject to U.S. federal income taxation at ordinary income tax rates on undistributed earnings and profits.

        While we do not believe that we should be treated as a controlled foreign corporation, or CFC, for U.S. federal income tax purposes, no assurances can be offered in this regard. We will generally be classified as a CFC if more than 50% of our outstanding ordinary shares, measured by reference to voting power or value, are owned (directly, indirectly or by attribution) by "10% U.S. Shareholders." For this purpose, a "10% U.S. Shareholder" is any U.S. person that owns directly, indirectly or by attribution, 10% or more of the voting power of our outstanding ordinary shares. If we are classified as a CFC, a 10% U.S. Shareholder may be subject to U.S. federal income taxation at ordinary income tax rates on all or a portion of our undistributed earnings and profits attributable to certain categories of passive income and certain other income described in Subpart F of the Code, and may also be subject to U.S. federal income taxation at ordinary income tax rates on any gain realized on a sale of ordinary shares, to the extent of our current and accumulated earnings and profits attributable to such shares.

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The CFC rules are complex, and U.S. persons that are, or may be, 10% U.S. Shareholders are urged to consult their own tax advisors regarding the possible application of the CFC rules to them in their particular circumstances.

If we were treated as a passive foreign investment company for U.S. federal income tax purposes, U.S. investors in our ordinary shares could be subject to adverse U.S. federal income tax consequences.

        For U.S. federal income tax purposes, a foreign corporation is classified as a passive foreign investment company, or PFIC, for any taxable year if either (i) 75% or more of its gross income for such taxable year is "passive income" (as defined for such purposes) or (ii) 50% or more of the value of the assets held by such corporation (based on an average of the quarterly values of the assets) during such taxable year is attributable to assets that produce passive income or that are held for the production of passive income.

        As discussed in "Material U.S. Federal Tax Considerations for Holders of Ordinary Shares," we do not believe that we are currently a PFIC, and we do not anticipate becoming a PFIC in the foreseeable future; however, no assurances can be offered in this regard. The tests for determining PFIC status are applied annually after the close of the taxable year. It is difficult to accurately predict future income and assets relevant to this determination and no ruling from the IRS or opinion of counsel has been or will be sought with respect to PFIC status. Whether we are a PFIC will depend on our particular facts and circumstances (such as the valuation of our assets, including goodwill and other intangible assets, the treatment of intercompany interest income, etc.) and may also be impacted by the application of the PFIC rules, which are subject to differing interpretations. The fair market value of our assets is expected to depend, in part, upon (a) the market price of our ordinary shares and (b) the composition of our income and assets, which will be impacted by how, and how quickly, we spend any cash that is raised in any financing transaction. Accordingly, we cannot assure U.S. holders that we are not, or will not become, a PFIC. If we should determine that we are a PFIC, we will attempt to notify U.S. holders, although there can be no assurance that we will be able to do so in a timely and complete manner. If we are a PFIC for any taxable year during which a U.S. holder holds our ordinary shares, we generally will continue to be treated as a PFIC with respect to such U.S. holder for all succeeding taxable years during which such holder holds our ordinary shares, although a U.S. holder may avoid some of the adverse effects of the PFIC regime by making a deemed sale election with respect to our ordinary shares after we have ceased being treated as a PFIC.

        If we are properly characterized as a PFIC, U.S. holders of our ordinary shares would be subject to adverse U.S. federal income tax consequences, such as ineligibility for any preferred tax rates on capital gains, or on actual or deemed dividends, interest charges on certain taxes treated as deferred, and additional annual reporting requirements under U.S. federal income tax laws and regulations. Whether or not U.S. holders of our ordinary shares make a timely mark-to-market election may impact the U.S. federal income tax consequences to U.S. holders with respect to the acquisition, ownership and disposition of our ordinary shares and any distributions such U.S. holders may receive. Investors should consult their own tax advisors regarding all aspects of the application of the PFIC rules to our ordinary shares.

Failure to comply with the tax laws of the United States, the United Kingdom or other jurisdictions, which laws are subject to potential legislative, judicial or administrative change and differing interpretations, possibly on a retroactive basis, may result in erroneous filings, negative impact to income and reputational damage.

        We and our Affiliates are subject to a range of taxes and tax audits. Tax and other regulatory authorities may disagree with tax positions taken by us and our Affiliates based on our, or their, interpretations of the relevant tax laws, which could result in erroneous filings, retroactive adverse impact on income, the loss of tax benefits and reputational damage. We will regularly assess the likelihood of favorable or unfavorable outcomes resulting from these examinations to determine the adequacy of our provision for income taxes, which will require estimates and judgments. Although we

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will make these tax estimates on a reasonable basis, there can be no assurance that the tax authorities will agree with such estimates and judgments. From time to time, we may have to engage in litigation to attempt to achieve the results reflected in our estimates, which may be time-consuming and expensive and may have other adverse impacts. There can be no assurance that we will be successful in any such litigation or that any final determination of our tax liability will not be materially different from the historical treatment reflected in our historical income tax provisions and accruals. Any future changes to tax laws or interpretations could have a material impact on our effective tax rate and subsequently our results of operations.

        While we believe that being incorporated in the United Kingdom should help us maintain a competitive worldwide effective corporate tax rate, we cannot give any assurance as to what our effective tax rate will be. This is because, among other things, of uncertainties regarding the tax policies of all the jurisdictions where we operate our business and uncertainties regarding the application to our structure, which is complex, of the tax laws of various jurisdictions, including, without limitation, the United States and the United Kingdom. Because of this uncertainty, our actual effective tax rate may vary from our expectation and that variance could be material. Additionally, the tax laws of the United States, the United Kingdom or other jurisdictions, or the administrative or judicial interpretations thereof, could change in the future, possibly with retroactive effect, and such changes could cause a material change in our effective tax rate.

If various U.S. federal legislative proposals and modifications to existing tax treaties between the U.S. and foreign countries are enacted, they could result in a material increase in our U.S. and state taxes.

        Proposals have been introduced in the U.S. Congress that, if ultimately enacted, could either limit treaty benefits on certain payments made by our Affiliates or their subsidiaries or subject the earnings from non-U.S. subsidiaries of our Affiliates to taxation, or both. We cannot predict the outcome of any specific legislative proposals. However, since we operate or have operations in a number of foreign jurisdictions, our plans for expansion or our results of operations in such jurisdictions could be adversely affected if any adopted proposals resulted in an increase in our tax burden, costs of our tax compliance or otherwise adversely affected our results of operations and cash flows.

Risks Related to This Offering

Our ordinary shares have no prior market, and our share price may decline after this offering.

        Although we intend to list our ordinary shares on the NYSE, an active public trading market for our ordinary shares may not develop or, if it develops, may not be maintained after this offering, and we cannot predict how liquid the market for our ordinary shares might become. Although certain of the underwriters have advised us that they intend to make a market in our ordinary shares, they are not obligated to do so. The underwriters may also discontinue any market making activities at any time, in their sole discretion, which could further negatively impact your ability to sell our ordinary shares or the prevailing market price at the time you choose to sell. If an active trading market does not develop, you may have difficulty selling your ordinary shares at an attractive price or at all. For example, the NYSE imposes certain securities trading requirements, including minimum trading price, minimum number of shareholders and minimum market capitalization. We and the representatives of the underwriters will negotiate to determine the initial public offering price. The initial public offering price may not reflect the price at which investors in the market will be willing to buy and sell our ordinary shares following this offering and may be higher than the trading price of our ordinary shares following this offering. As a result, there can be no assurance that following this offering our ordinary shares will trade at a price equal to or greater than the offering price.

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The trading price of our ordinary shares may be volatile, and you may not be able to sell your ordinary shares at or above the initial public offering price.

        The trading price and volume of our ordinary shares may be highly volatile and could be subject to wide fluctuations in response to various factors. Some of the factors that may cause the trading price and volume of our ordinary shares to fluctuate include:

•

fluctuations in our annual or quarterly financial results, level of net client cash inflows or outflows or our AUM or the annual or quarterly financial results of companies perceived to be similar to us;



•

changes in, or a failure to meet, estimates of our financial results or changes in recommendations by securities analysts;



•

low number of ordinary shares available for public trading;



•

the entrance into the market and success of new competitors;



•

our acquisition or disposition of Affiliates;



•

our ability to hire and retain qualified personnel, including key personnel;



•

changes in the regulatory environment related to our business and industry;



•

litigation or regulatory actions involving us;



•

investors' general perception of us or the investment management industry generally;



•

performance of our Affiliates' investment products on an absolute basis or relative to benchmarks or peers;



•

publication of research reports about us or the investment management industry, or the failure of securities analysts to cover our ordinary shares after this offering;



•

adverse market reactions to any indebtedness we may incur or securities we may issue in the future;



•

actions by shareholders;



•

changes in market valuations of similar companies;



•

changes in general economic, industry and market conditions; and



•

regulatory compliance costs.

        In addition, if the stock market in general experiences a loss of investor confidence, the trading price of our ordinary shares could decline for reasons unrelated to our business, financial condition or results of operations. The price of our ordinary shares may be impacted by changes in securities prices to a greater extent than businesses outside of our industry. This is because as securities prices in general decline, the price of our ordinary shares may be impacted not only by this general decline but also by the impact of the general decline on our assets under management and revenue.

        Some companies that have had volatile market prices for their securities have had securities class actions filed against them. If a lawsuit were filed against us, regardless of its merits or outcome, it likely would result in substantial costs and divert management's attention and resources. This could have a material adverse effect on our business, results of operations and financial condition.

Future sales of our ordinary shares by us, OMGUK or other shareholders could cause our share price to decline.

        If we, OMGUK or other shareholders sell, or indicate an intention to sell, or there is a perception that they might sell, substantial amounts of our ordinary shares in the public market after the contractual lock-up agreements described below and other restrictions on resale lapse, the trading price of our ordinary shares could decline below the initial public offering price or the then-current trading level. Upon completion of this offering we expect to have 120,000,000 ordinary shares outstanding

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(excluding any ordinary shares granted to employees under our equity incentive plans). Of these shares,            ordinary shares will be subject to a 180-day contractual lock-up (subject to extension) with the underwriters. Certain of the representatives of the underwriters may permit our officers, directors, employees and current shareholders who are subject to the contractual lock-up to sell ordinary shares or to demand piggy-back registration rights prior to the expiration of the lock-up agreements.

        Sales by OMGUK or other shareholders or the possibility that these sales may occur also may make it more difficult for us to raise additional capital by selling equity securities in the future, at a time and price that we deem appropriate.

        Pursuant to a registration rights agreement that we will enter into with our Parent, we will agree to use our reasonable best efforts to file registration statements from time to time for the sale of ordinary shares held by OMGUK now or in the future. See "Certain Relationships and Related Party Transactions—Relationship with Our Parent and OMGUK Following This Offering—Parent Registration Rights Agreement." See also "Ordinary Shares Eligible for Future Sale" for further details regarding the number of ordinary shares eligible for sale in the public market after this offering.

        We cannot predict the size of future issuances of our ordinary shares or the effect, if any, that future issuances and sales of our ordinary shares may have on the market price of our ordinary shares. Sales or distributions of substantial amounts of our ordinary shares, including shares issued in connection with an acquisition, or the perception that such sales or distributions could occur, may cause the market price of our ordinary shares to decline.

The pro forma net tangible book value per share of our ordinary shares is lower than the offering price of our ordinary shares. You will experience substantial dilution as a result of investing in this offering.

        The initial public offering price per share is substantially higher than the pro forma net tangible book value per share of our ordinary shares outstanding. As a result, investors purchasing ordinary shares in this offering will experience immediate substantial dilution of $        comparing the tangible book value per ordinary share to the offering price (based on the mid-point of the range on the front cover of the prospectus).

We will incur additional costs due to operating as a public company whose ordinary shares are publicly traded in the United States, and our management expects to devote substantial time to compliance with our public company legal and reporting obligations.

        As a public company whose ordinary shares are traded in the United States, we will incur additional legal, accounting and other expenses that we did not incur as a private company. In addition, we will be subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and will be required to implement specific corporate governance practices and adhere to a variety of reporting requirements under the Sarbanes-Oxley Act of 2002, or Sarbanes-Oxley, and the related rules and regulations of the SEC, as well as the rules of the NYSE. The Exchange Act will require us to file annual, quarterly and current reports with respect to our business and financial condition. Our management and other personnel will need to devote substantial time to compliance with our public company obligations. Moreover, these rules and regulations will increase our legal and financial compliance costs and will make some activities more time-consuming and costly. For example, we expect these new rules and regulations to make it more difficult and more expensive for us to obtain director and officer liability insurance, and we may be required to incur additional costs to maintain the same or similar coverage.

        In addition, Sarbanes-Oxley requires, among other things, that we maintain effective internal control over financial reporting and disclosure controls and procedures. In particular, commencing with our Annual Report on Form 10-K for fiscal year 2015, we must perform system and process evaluation and testing of our internal control over financial reporting to allow management to report on the effectiveness of our internal control over financial reporting, as required by Section 404 of Sarbanes-Oxley, and obtain an auditor attestation as to the effectiveness of our internal controls. Our testing may

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reveal deficiencies in our internal control over financial reporting that are deemed to be material weaknesses. Our compliance with Section 404 will require that we incur additional accounting expense and expend additional management time on compliance-related issues. Moreover, if we are not able to comply with the requirements of Section 404 in a timely manner, or if we identify deficiencies in our internal control over financial reporting that are deemed to be material weaknesses, the market price of our ordinary shares could decline, and we could be subject to sanctions or investigations by the NYSE, the SEC or other regulatory authorities, which would require additional financial and management resources.

        As a public company we will also need to enhance our investor relations, legal, financial reporting, treasury and corporate communications functions. We have historically presented our Consolidated Financial Statements in accordance with International Financial Reporting Standards, or IFRS, but have presented our Consolidated Financial Statements in this prospectus, and will present our Consolidated Financial Statements after the consummation of this offering, in accordance with U.S. GAAP. These additional efforts may strain our resources and divert management's attention from other business concerns, which could have a material adverse effect on our business, financial condition and results of operations.

Risks Related to Being an English Company Listing Ordinary Shares

The rights of our shareholders may differ from the rights typically offered to shareholders of a U.S. corporation organized in Delaware.

        We are incorporated under the laws of England and Wales. The rights of holders of our ordinary shares are governed by English law, including the provisions of the Companies Act 2006, and by our articles of association. These rights differ in certain respects from the rights of shareholders in typical U.S. corporations organized in Delaware. The principal differences are set forth in "Description of Share Capital—Differences in Corporate Law."

U.S. investors may have difficulty enforcing civil liabilities against the Company, our directors or members of senior management and the experts named in this prospectus.

        We are incorporated under the laws of England and Wales. Several of our directors reside outside the United States and all or a substantial portion of the assets of such persons are located outside the United States. As a result, it may be difficult for you to serve legal process on us or our directors or have any of them appear in a U.S. court. The United States and the United Kingdom do not currently have a treaty providing for the recognition and enforcement of judgments, other than arbitration awards, in civil and commercial matters. The enforceability of any judgment of a U.S. federal or state court in the United Kingdom will depend on the laws and any treaties in effect at the time, including conflicts of laws principles (such as those bearing on the question of whether a U.K. court would recognize the basis on which a U.S. court had purported to exercise jurisdiction over a defendant). In this context, there is doubt as to the enforceability in the United Kingdom of civil liabilities based solely on the federal securities laws of the United States. In addition, awards for punitive damages in actions brought in the United States or elsewhere may be unenforceable in the United Kingdom. An award for monetary damages under the U.S. securities laws would likely be considered punitive if it did not seek to compensate the claimant for loss or damage suffered and was intended to punish the defendant.

English law and provisions in our articles of association may have anti-takeover effects that could discourage an acquisition of us by others, even if an acquisition would be beneficial to our shareholders, and may prevent attempts by our shareholders to replace or remove our current management.

        Certain provisions of English law and our articles of association (as in effect following the completion of this offering) may have the effect of delaying or preventing a change in control of us or

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changes in our management. For example, English law and our articles of association include, or will include, provisions that:

•

establish an advance notice procedure for shareholder approvals to be brought before an annual meeting of our shareholders, including proposed nominations of persons for election to our Board of Directors; and



•

provide that vacancies on our Board of Directors may, in certain specified circumstances, be filled only by a majority of directors then in office, even though less than a quorum.

        These provisions, alone or together, could delay or prevent hostile takeovers and changes in control or changes in our management. In addition, these provisions may adversely affect the market price of our ordinary shares or inhibit fluctuations in the market price of our ordinary shares that could otherwise result from actual or rumored takeover attempts.

        The U.K. City Code on Takeovers and Mergers, or the Takeover Code, applies, among other things, to an offer for a public company whose registered office is in the United Kingdom (or the Channel Islands or the Isle of Man) and whose securities are not admitted to trading on a regulated market in the United Kingdom (or the Channel Islands or the Isle of Man) if the company is considered by the Panel on Takeovers and Mergers, or the Takeover Panel, to have its place of central management and control in the United Kingdom (or the Channel Islands or the Isle of Man). This is known as the "residency test." Under the Takeover Code, the Takeover Panel will determine whether we have our place of central management and control in the United Kingdom by looking at various factors, including the structure of our Board of Directors, the functions of the directors and where they are resident.

        If at the time of a takeover offer the Takeover Panel determines that we have our place of central management and control in the United Kingdom, we would be subject to a number of rules and restrictions, including but not limited to the following: (i) our ability to enter into deal protection arrangements with a bidder would be extremely limited; (ii) we might not, without the approval of our shareholders, be able to perform certain actions that could have the effect of frustrating an offer, such as issuing shares or carrying out acquisitions or disposals; and (iii) we would be obliged to provide equality of information to all bona fide competing bidders.

        Following the completion of this offering, our Parent will be interested in over 50% of our voting share capital, and therefore, if the Takeover Panel were to determine that we were subject to the Takeover Code, our Parent would be able to increase its aggregate holding in us without triggering the requirement under Rule 9 of the Takeover Code to make a cash offer for the outstanding shares in the Company.

        The Takeover Panel has confirmed to our representatives that, on the basis of our planned board of directors, it does not consider the Takeover Code to apply to the Company, although that position is subject to change if our center of management and control is subsequently found to move to the U.K.

We will be subject to data protection laws under U.K. legislation, and any breaches of such legislation could adversely affect our business, reputation, results of operations and financial condition.

        Our ability to obtain, retain and otherwise manage personal data is governed by data protection and privacy requirements and regulatory rules and guidance. In the U.K., we must comply with the Data Protection Act 1998 in relation to processing certain personal data. The application of data privacy laws is often uncertain, and as business practices are challenged by regulators, private litigants and consumer protection agencies, it is possible that these laws may be interpreted and applied in a manner that is inconsistent with our data protection practices. Additionally, under European data protection laws, distributing personal data into the United States may constitute an offense.

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Pre-emption rights for U.S. and other non-U.K. holders of shares may be unavailable.

        In the case of certain increases in our issued share capital, under English law, existing holders of shares are entitled to pre-emption rights to subscribe for such shares, unless shareholders dis-apply such rights by a special resolution at a shareholders' meeting. These pre-emption rights will have been dis-applied by our shareholder prior to completion of the offering and we shall propose equivalent resolutions in the future once the initial period of dis-application has expired. However, OMGUK will have pre-emption rights, subject to certain exceptions, until it ceases to own more than 7% of our outstanding ordinary shares. In any event, U.S. holders of ordinary shares in U.K. companies are customarily excluded from exercising any such pre-emption rights they may have, unless a registration statement under the Securities Act is effective with respect to those rights, or an exemption from the registration requirements thereunder is available. We cannot assure prospective U.S. investors that any exemption from the registration requirements of the Securities Act or applicable non-U.S. securities laws would be available to enable U.S. or other non-U.K. holders to exercise such pre-emption rights or, if available, that we will utilize any such exemption.

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