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

FORM 10-Q

Commission File Number: 001-34516

Cowen Group, Inc.
(Exact name of registrant as specified in its charter)

(212) 845-7900
(Registrant's telephone number, including area code)

        Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

        Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes o    No o

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

        Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o    No ý

APPLICABLE ONLY TO CORPORATE ISSUERS:

        As of May 9,August 8, 2011 there were 75,668,292116,291,426 shares of the registrant's common stock outstanding.

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Special Note Regarding Forward-Looking Statements

        We have made statements in this Quarterly Report on Form 10-Q (including in "Management's Discussion and Analysis of Financial Condition and Results of Operations") that are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. In some cases, you can identify these statements by forward-looking terms such as "may," "might," "will," "would," "could," "should," "expect," "plan," "anticipate," "believe," "estimate," "predict," "project," "possible," "potential," "intend," "seek" or "continue," the negative of these terms and other comparable terminology or similar expressions. In addition, our management may make forward-looking statements to analysts, representatives of the media and others. These forward-looking statements represent only the Company's beliefs regarding future events (many of which, by their nature, are inherently uncertain and beyond our control) and are predictions only, based on our current expectations and projections about future events. There are important factors that could cause our actual results, level of activity, performance or achievements to differ materially from those expressed or implied by the forward-looking statements. In particular, you should consider the risks contained in Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2010.

        Although we believe the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, level of activity, performance or achievements. Moreover, neither we nor any other person assumes responsibility for the accuracy or completeness of any of these forward-looking statements. You should not rely upon forward-looking statements as predictions of future events. We undertake no obligation to update any of these forward-looking statements after the date of this filing to conform our prior statements to actual results or revised expectations.

        Unaudited Condensed Consolidated Financial Statements are presented for the three months and six months ended March 31,June 30, 2011 and 2010. The Condensed Consolidated Financial Statements as of December 31, 2010 were audited.

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PART I. FINANCIAL INFORMATION

Item 1.    Unaudited Condensed Consolidated Financial Statements

Cowen Group, Inc.

Condensed Consolidated Statements of Financial Condition

(in thousands, except share and per share data)

(unaudited)

The accompanying notes are an integral part of these condensed consolidated financial statements.

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Cowen Group, Inc.

Condensed Consolidated Statements of Operations

(in thousands, except per share data)

(unaudited)

The accompanying notes are an integral part of these condensed consolidated financial statements.

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Cowen Group, Inc.

Condensed Consolidated Statements of Changes in Equity

(in thousands, except share data)

(unaudited)

The accompanying notes are an integral part of these condensed consolidated financial statements.

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Cowen Group, Inc.

Condensed Consolidated Statements of Cash Flows

(in thousands)

(unaudited)

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Cowen Group, Inc.

Condensed Consolidated Statements of Cash Flows (Continued)

(in thousands)

(unaudited)

The accompanying notes are an integral part of these condensed consolidated financial statements.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements

(unaudited)

1. Organization and Business

        Cowen Group, Inc., a Delaware corporation, was formed on June 1, 2009 in connection with the Transaction Agreement and Agreement and Plan of Merger ("Transaction Agreement"), dated as of June 3, 2009, by and among Cowen Holdings, Inc., ("Cowen Holdings," formerly Cowen Group, Inc.), Lexington Merger Corp., Ramius LLC ("Ramius," formerly Park Exchange LLC) and RCG Holdings LLC ("RCG," formerly Ramius LLC).

        Cowen Group, Inc. is a diversified financial services firm and, together with its consolidated subsidiaries (collectively, "Cowen Group" or the "Company"), provides alternative investment management, investment banking, research, market-making and sales and trading services through its two business segments: alternative investment management and broker-dealer. The alternative investment management segment includes hedge funds, replication products, mutual funds, managed futures funds, fund of funds, real estate, funds, healthcare royalty funds, and cash management services and mortgage advisory services, offered primarily under the Ramius name. The broker-dealer segment offers industry focusedindustry-focused investment banking services for growth-oriented companies, including advisory and global credit markets origination and domain knowledge-driven research, and a sales and trading platform for institutional investors, primarily under the Cowen name.name and an ETF market-making business, both domestically and internationally.

2. Acquisition

        The acquisition of LaBranche & Co Inc. ("LaBranche") by the Company was consummated pursuant to the terms of the Agreement and Plan of Merger ("Merger Agreement"), dated as of February 16, 2011, after the market close on June 28, 2011. LaBranche Capital, LLC (LCAP), which was renamed "Cowen Capital LLC" following consummation of the acquisition, was a wholly owned subsidiary of LaBranche and is now a wholly-owned subsidiary of the Company, is a registered broker-dealer and Financial Industry Regulatory Authority ("FINRA") member firm that operates as a market-maker in Exchange Traded Funds ("ETFs"), engages in hedging activities in options, ETFs, structured notes, foreign currency securities and futures related to its market-making operations and also conducts principal trading activities in these securities. Prior to the acquisition, LaBranche discontinued certain operations in its market-making segment, including upstairs options market-making on various exchanges and electronic market-making in the International Securities Exchange. As of the close of market on June 28, 2011, LaBranche stock was delisted and no longer trades on the New York Stock Exchange.

        Under the terms of the Merger Agreement, each outstanding share of LaBranche was converted into 0.9980 shares of Cowen Class A common stock (the "Exchange Ratio"). The consideration received by LaBranche's shareholders was valued at approximately $156 million in the aggregate, based on the closing price of Cowen Class A common stock on the NASDAQ Global Select Market of $3.82 on June 28, 2011. This is based on 40,931,997 shares of LaBranche stock that were outstanding on the date of the completion of the acquisition.

        The acquisition was accounted for under the acquisition method of accounting in accordance with accounting principles generally accepted in the United States of America ("US GAAP"). In this case, the acquisition was accounted for as an acquisition by Cowen of LaBranche. As such, results of operations for LaBranche are included in the accompanying condensed consolidated statements of operations since the date of acquisition, and the assets acquired and liabilities assumed were recorded at their estimated fair values. The fair value of Cowen shares issued to LaBranche shareholders was the

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Acquisition (Continued)

purchase consideration for the acquisition. Based on the June 28, 2011 preliminary purchase price allocation, the fair value of the net identifiable assets acquired and liabilities assumed amounted to $175.9 million, (excluding $2.3 million non-compete agreements acquired) exceeding the fair value of the preliminary purchase price of $156 million. As a result, the Company recognized a preliminary, nonrecurring bargain purchase gain of approximately $22.2 million in the second quarter of 2011, which is included in other income in the condensed consolidated statements of operations for the three and six month periods ended June 30, 2011. The Company's share price has traded below its book value for a substantial part of the last 52 weeks, and as the preliminary purchase consideration (the Exchange Ratio) was determined based on the stock price of Cowen on June 28, 2011, the purchase price allocation based on the fair value of LaBranche's net assets at acquisition date reflected in these condensed consolidated financial statements has resulted in a bargain purchase gain.

        The Company is currently in the process of finalizing the valuation for certain acquired assets of LaBranche; therefore, the fair value measurements at June 28, 2011 and the gain on acquisition of business are preliminary and subject to further adjustment. The allocation of the purchase price to the net assets acquired will be finalized as necessary, up to one year after the acquisition closing date, as information becomes available. The following table summarizes the preliminary purchase price allocation of net tangible and intangible assets acquired as of June 28, 2011:

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Acquisition (Continued)

        The Company believes that all of the acquired receivables and contractual amounts receivable as reflected above in the preliminary allocation of the purchase price are recorded at fair value and are expected to be collected in full.

        The Company recognized approximately $0.6 million and $2.3 million of acquisition-related costs, including legal, accounting, and valuation services for the three months and six months ended June 30, 2011, respectively. These costs are included in professional, advisory and other fees and other expenses in the condensed consolidated statements of operations.

        As of June 30, 2011, the estimated fair value of the Company's intangibles, as acquired through the acquisition, is $3 million. In addition, non-compete agreements for the amount of $2.3 million, were negotiated as part of the acquisition, which have been recognized separately from the acquisition of assets and liabilities assumed in accordance U.S. GAAP. The total non-compete agreements acquired of $2.5 million, have been included within Intangible assets, net in the condensed consolidation statements of financial condition. The allocation of the intangibles is as follows:

        Amortization expense for the three and six months ended June 30, 2011, respectively, is immaterial. The estimated amortization expense related to these intangible assets in future years is as follows:

        Included in the accompanying condensed consolidated statements of operations for the three months and six months ended June 30, 2011 are revenues of $0.2 million and a net income of $0.2 million related to LaBranche's results of operations for the period from June 29, 2011 through June 30, 2011.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Acquisition (Continued)

        The following unaudited supplemental pro forma information presents condensed consolidated financial results for the six month periods as if the acquisition was completed as of January 1, 2010. This supplemental pro forma information has been prepared for comparative purposes only and is not intended to be indicative of what the Company's results would have been had the acquisition been completed on January 1, 2010, nor does it purport to be indicative of any future results.

3. Significant Accounting Policies

a.     Basis of presentation

        These unaudited condensed consolidated financial statements and related notes have been prepared in accordance with accounting principles generally accepted in the United States of America ("US GAAP")GAAP and the rules and regulations of the U.S. Securities and Exchange Commission ("SEC") related to interim financial statements. Results for interim periods should not be considered indicative of results for any other interim period or for the full year. These financial statements should be read in conjunction with the audited condensed consolidated financial statements as of December 31, 2010 and 2009 and for the years ended December 31, 2010, 2009, and 2008, included in the Form 10-K of Cowen Group as filed with the SEC on March 14, 2011. The financial information contained herein is unaudited; however, management believes all adjustments have been made that are necessary for a fair presentation of the results for the interim periods. The year end condensed balance sheet data was derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States of America. All material intercompany transactions and balances have been eliminated in consolidation. Certain fund entities that are consolidated in these condensed consolidated financial statements, as further discussed below, are not subject to these consolidation provisions with respect to their own investments pursuant to their specialized accounting.

        The Company serves as the managing member/general partner and/or investment manager to affiliated fund entities which it sponsors and manages. Funds in which the Company has a substantive, controlling general partner interest are consolidated with the Company pursuant to US GAAP as described below. Consequently, the Company's condensed consolidated financial statements reflect the assets, liabilities, income and expenses of these funds on a gross basis. The ownership interests in these funds which are not owned by the Company are reflected as redeemable non-controlling interests in consolidated subsidiaries in the accompanying condensed consolidated financial statements. The management fees and incentive income earned by the Company from these funds are eliminated in consolidation.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2.3. Significant Accounting Policies (Continued)

b.     Principles of consolidation

        The Company determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting operating entity ("VOE") or a variable interest entity ("VIE") under US GAAP.

        Voting Operating Entities—VOEs are entities in which (i) the total equity investment at risk is sufficient to enable the entity to finance its activities independently and (ii) the equity holders at risk have the obligation to absorb losses, the right to receive residual returns and the right to direct the activities of the entity that most significantly impact the entity's economic performance. VOEs are consolidated in accordance with Financial Accounting Standards Board ("FASB") accounting standards. In accordance with these standards, the Company presently consolidates five funds deemed to be VOEs for which it acts as the general partner and investment manager.

        Under FASB accounting standards, the usual condition for a controlling financial interest in an entity is ownership of a majority voting interest. Accordingly, the Company consolidates VOEs in which it owns a majority of the entity's voting shares or units. FASB accounting standards also provide that a general partner of a limited partnership (or a managing member, in the case of a limited liability company) is presumed to control the partnership, and thus should consolidate it, unless a simple majority of the limited partners has the right to remove the general partner without cause or to terminate the partnership. In accordance with these standards, the Company presently consolidates five funds deemed to be VOEs for which it acts as the general partner.partner and investment manager.

        As of March 31,June 30, 2011 the Company consolidates the following funds (the "Consolidated Funds"): Ramius Enterprise LP ("Enterprise LP"), Ramius Multi-Strategy FOF LP ("Multi-Strat FOF"), Ramius Vintage Multi-Strategy FOF LP ("Vintage LP"), Ramius Levered Multi-Strategy FOF LP ("Levered FOF"), and RTS Global 3x Fund LP ("RTS Global 3x").

        In addition, RCG Linkem II LLC was consolidated when it first commenced operations during the second quarter of 2011. The Company determined that it exercises control over RCG Linkem II LLC as it acts as a managing member of this entity.

        Variable Interest Entities—VIEs are entities that lack one or more of the characteristics of a VOE. In accordance with FASB accounting standards, an enterprise must consolidate all VIEs of which it is the primary beneficiary. Under the new FASB consolidation model for VIEs, an enterprise that (1) has the power to direct the activities of a VIE that most significantly impacts the VIE's economic performance, and (2) has an obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE, is considered to have a controlling financial interest in the VIE and thus is required to consolidate it.

        However, the FASB has deferred the application of the new consolidation model for VIEs that meet the following conditions; (a) the entity has all the attributes of an investment company as defined under AICPA Audit and Accounting Guide,Investment Companies, or does not have all the attributes of an investment company but is an entity for which it is acceptable based on industry practice to apply measurement principles that are consistent with the AICPA Audit and Accounting Guide,Investment Companies, (b) the reporting entity does not have explicit or implicit obligations to fund any losses of the entity that could potentially be significant to the entity, and (c) the entity is not a securitization entity, asset-backed financing entity or an entity that was formerly considered a qualifying special-purpose entity. The Company's involvement with its funds is such that all three of the above conditions are met. Where the VIEs have qualified for the deferral, the analysis is based on previous

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2.3. Significant Accounting Policies (Continued)

are met. Where the VIEs have qualified for the deferral, the analysis is based on previous consolidation rules. These rules require an analysis to (a) determine whether an entity in which the Company holds a variable interest is a variable interest entity and (b) whether the Company's involvement, through holding interests directly or indirectly in the entity or contractually through other variable interests (e.g., management and performance related fees), would be expected to absorb a majority of the VIE's expected losses, receive a majority of the VIEs expected residual returns, or both. If this condition is met, the Company is considered to have a controlling financial interest in the VIE and thus is required to consolidate it. Under both guidelines, the Company determines whether it is the primary beneficiary of a VIE at the time it becomes involved with a variable interest entity and reconsiders that conclusion continuously.

        The Company determines whether it is the primary beneficiary of a VIE by performing a qualitative and/or quantitative analysis of the VIE that includes a review of, among other things, its capital structure, terms of any contracts between the Company and the VIE, which interests create or absorb variability, related party relationships and the design of the VIE. As of March 31,June 30, 2011, the Company does not consolidate any VIEs.

        The Company has determined that it no longer exercises control over Cowen Healthcare Royalty GP, LLC (the "CHRP GP") as it no longer acts as a managing member of this entity, and the beginning with the first quarter of 2010, no longer consolidates this entity. The Company now accounts for its investment in the CHRP GP under the equity method of accounting.

        As at March 31,June 30, 2011, the Company holds a variable interest in Ramius Enterprise Master Fund Ltd ("Enterprise Master"), Ramius Multi-Strategy Master FOF LP and Ramius Vintage Multi-Strategy Master FOF LP (the "Unconsolidated Master Funds") through three of its Consolidated Funds: Enterprise LP, Multi-Strat FOF and Vintage FOF (the "Consolidated Feeder Funds"), respectively. Investment companies like the Consolidated Feeder Funds, which account for their investments under the specialized industry accounting guidance for investment companies prescribed under FASB accounting standards, are not subject to the consolidation provisions for their investments. Therefore, the Company has not consolidated the Unconsolidated Master Funds.

        In the ordinary course of business, the Company also sponsors various other entities that it has determined to be VIEs. These VIEs are primarily funds and real estate entities for which the Company serves as the general partner, managing member and/or investment manager with decision-making rights.

        The Company does not consolidate any of the funds or real estate entities that are VIEs as it has concluded that it is not the primary beneficiary in each instance. Fund investors are entitled to all of the economics of these VIEs with the exception of the management fee and incentive income, if any, earned by the Company. The Company's involvement with funds and real estate entities that are unconsolidated VIEs is limited to providing investment management services in exchange for management fees and incentive income. Although the Company may advance amounts and pay certain expenses on behalf of the funds and real estate entities that it considers to be VIEs, it does not provide, nor is it required to provide, any type of substantive financial support to these entities outside of regular investment management services.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

3. Significant Accounting Policies (Continued)

        The total assets and liabilities of the variable interest entities for which the Company has concluded that it holds a variable interest, but for which it is not the primary beneficiary, are

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Significant Accounting Policies (Continued)

$315.3 $296 million and $1$1.9 million as of March 31,June 30, 2011 and $383.3 million and $26.7 million as of December 31, 2010, respectively. In addition, the maximum exposure relating to these variable interest entities as of March 31,June 30, 2011 was $256.9$236.7 million, all of which is in other investments, at fair value and as of December 31, 2010 was $307.8 million, of which $307.2 million is included in other investments, at fair value and $0.6 million is included in due from related parties in the Company's condensed consolidated statements of financial condition, respectively. The Consolidated Feeder Funds' maximum exposure to loss related to their respective Unconsolidated Master Funds at March 31,June 30, 2011 and December 31, 2010 was limited to their investmentinvestments in their respective Unconsolidated Master Funds. See Note 45 for further information regarding the Company's investments.

        Equity Method Investments—For operating entities over which the Company exercises significant influence but which do not meet the requirements for consolidation as outlined above, the Company uses the equity method of accounting. The Company's investments in equity method investees are recorded in other investments in the condensed consolidated statements of financial condition. The Company's equity in earnings or losses from equity method investees is included in net gains (losses) on securities, derivatives and other investments in the condensed consolidated statements of operations.

        The Company evaluates for impairment its equity method investments whenever events or changes in circumstances indicate that the carrying amounts of such investments may not be recoverable. The difference between the carrying value of the equity method investment and its estimated fair value is recognized as an impairment when the loss in value is deemed other than temporary.

        Cost Method Investments—When the Company does not have a controlling financial interest and does not exert significant influence over an entity's operating and financial policies, but has an investment in private equity for which market quotations are not readily available and is not otherwise accounted for at fair value, the Company accounts for its investment in accordance with the cost method of accounting.

        Other—If the Company does not consolidate an entity, apply the equity method of accounting or account for an investment under the cost method, the Company accounts for all other debt and marketable equity securities which are bought and held principally for the purpose of selling them in the near term as trading securities in accordance with FASB accounting standards, at fair value with unrealized gains (losses) resulting from changes in fair value reflected within net gains (losses) on securities, derivatives and other investments in the condensed consolidated statements of operations.

        Retention of Specialized Accounting—The Consolidated Funds are investment companies and apply specialized industry accounting for investment companies. The Company has retained this specialized accounting for these funds pursuant to FASB accounting standards. The Consolidated Funds report their investments on the condensed consolidated statements of financial condition at their estimated fair value, with unrealized gains (losses) resulting from changes in fair value reflected as a component of operations. Accordingly, the accompanying condensed consolidated financial statements reflect different accounting policies for investments depending on whether or not they are held through a consolidated investment company. In addition, the Company's broker-dealer subsidiaries, Ramius Securities LLC ("Ramius Securities") and Cowen and Company, LLC ("Cowen and Company"), Cowen Capital LLC, Cowen International Trading Limited,

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

3. Significant Accounting Policies (Continued)

Cowen and Company (Asia) Limited ("CCAL"), and Cowen Structured Products Hong Kong Limited, and apply the specialized industry accounting for brokers and dealers in securities also prescribed under FASB accounting standards. The Company also has retained this specialized accounting in consolidation.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Significant Accounting Policies (Continued)

c.     Use of estimates

        The preparation of the condensed consolidated financial statements in conformity with GAAP requires the management of the Company to make estimates and assumptions that affect the fair value of securities and other investments, the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, the accounting for goodwill and identifiable intangible assets and the reported amounts of revenues and expenses during the reporting period. Actual results could materially differ from those estimates.

d.     Valuation of investments and derivative contracts

        The FASB accounting standards establish a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1 measurements) and the lowest priority to unobservable inputs (level 3 measurements). The three levels of the fair value hierarchy are as follows:

        Inputs are used in applying the various valuation techniques and broadly refer to the assumptions that market participants use to make valuation decisions, including assumptions about risk. Inputs may include price information, volatility statistics, specific and broad credit data, liquidity statistics, and other factors. A financial instrument's level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. However, the determination of what constitutes "observable" requires significant judgment by the Company. The Company considers observable data to be that market data which is readily available, regularly distributed or updated, reliable and verifiable, not proprietary, and provided by independent sources that are actively involved in the relevant market. The categorization of a financial instrument within the hierarchy is based upon the pricing transparency of the instrument and does not necessarily correspond to the Company's perceived risk of that instrument.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

3. Significant Accounting Policies (Continued)

        The Company and its operating company subsidiaries act as the manager for the Consolidated Funds. Both the Company and the Consolidated Funds hold certain investments which are valued by the Company, acting as the investment manager. The fair value of these investments is generally estimated based on proprietary models developed by the Company, which include discounted cash flow analyses, public market comparables, and other techniques and may be based, at least in part, on independently sourced market information. The material estimates and assumptions used in these models include the timing and expected amount of cash flows, the appropriateness of discount rates

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Significant Accounting Policies (Continued)

used, and, in some cases, the ability to execute, timing of, and estimated proceeds from expected financings. Significant judgment and estimation goes into the selection of an appropriate valuation methodology as well as the assumptions used in these models, and the timing and actual values realized with respect to investments could be materially different from values derived based on the use of those estimates. The valuation methodologies applied impact the reported value of the Company's investments and the investments held by the Consolidated Funds in the condensed consolidated financial statements. Certain of the Company's investments are relatively illiquid or thinly traded and may not be immediately liquidated on demand if needed. Fair values assigned to these investments may differ significantly from the fair values that would have been used had a ready market for the investments existed and such differences could be material.

        The Company primarily uses the "market approach" valuation technique to value its financial instruments measured at fair value. In determining an instrument's placement within the hierarchy, the Company separates the Company's financial instruments into three categories: securities, derivative contracts and other investments. To the extent applicable, each of these categories can further be divided between those held long or sold short.

        Securities—Securities whose values are based on quoted market prices in active markets for identical assets, and are therefore classified in level 1 of the fair value hierarchy, include active listed equities, certain U.S. government and sovereign obligations, ETF's and certain money market securities. The Company does not adjust the quoted price for such instruments, even in situations where the Company holds a large position and a sale could reasonably impact the quoted price.

        Certain positions for which there is a limited market, consisting primarily of convertible debt, corporate debt and loans, are stated at fair value. The estimated fair values assigned by management are determined in good faith and are based on available information considering, among other things, quotations provided by published pricing services, counterparties and other market participants, and pricing models using quoted inputs, and do not necessarily represent the amounts which might ultimately be realized. Such positions that trade in markets that are not considered to be active, but are valued based on quoted market prices, dealer quotations or alternative pricing sources which are supported by observable inputs are classified within level 2. As level 2 investments include positions that are not traded in active markets and/or are subject to transfer restrictions, valuations may be adjusted to reflect illiquidity and/or non-transferability.

        Derivative contracts—Derivative contracts can be exchange-traded or privately negotiated over-the-counter ("OTC"). Exchange-traded derivatives, such as futures contracts and exchange traded option contracts, are typically classified within level 1 or level 2 of the fair value hierarchy depending on whether or not they are deemed to be actively traded. OTC derivatives, such as generic forwards, swaps and options, have inputs which can generally be corroborated by market data and are therefore classified within level 2. Derivative contracts are included within other assets or accounts payable, accrued expenses and other liabilities on the consolidated statements of financial condition. The Company's direct involvement with derivative financial instruments include credit default swaps, futures, equity swaps, options and warrants and rights which are included within securities owned, at fair value in the condensed consolidated statements of financial condition.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2.3. Significant Accounting Policies (Continued)

swaps and options, have inputs which can generally be corroborated by market data and are therefore classified within level 2. Futures and equity swap derivative contracts are included within other assets on the condensed consolidated statements of financial condition and all other derivatives are included within securities owned, at fair value on the condensed consolidated statements of financial condition.

        Other investments—Other investments consist primarily of portfolio funds, real estate investments and equity method investments, which are valued as follows:

i.

Portfolio funds—Portfolio funds ("Portfolio Funds") include interests in funds and investment companies managed by the Company or its affiliates. The Company follows an accounting pronouncement regarding fair value measurements and disclosures relating to investments in certain entities that calculate net asset value ("NAV") per share (or its equivalent). The guidance permits, as a practical expedient, an entity holding investments in certain entities that either are investment companies as defined by the AICPA Audit and Accounting Guide, Investment Companies, or have attributes similar to an investment company, and calculate net asset value per share or its equivalent for which the fair value is not readily determinable, to measure the fair value of such investments on the basis of that NAV per share, or its equivalent, without adjustment.

The Company categorizes its investments in Portfolio Funds within the fair value hierarchy dependent on the ability to redeem the investment. If the Company has the ability to redeem its investment at NAV at the measurement date or within the near term, the Portfolio Fund is categorized as a Level 2 fair value measurement. If the Company does not know when it will have the ability to redeem its investment or cannot do so in the near term, the Portfolio Fund is categorized as a Level 3 fair value measurement. See Note 45 and Note 56 for further details of the Company's investments in Portfolio Funds.

ii.

Real estate investments—Real estate investments are valued at estimated fair value. The fair value of real estate investments are estimated based on the price that would be received to sell an asset in an orderly transaction between marketplace participants at the measurement date. Real estate investments without a public market are valued based on assumptions and valuation techniques used by the Company. Such valuation techniques may include discounted cash flow analysis, prevailing market capitalization rates or earning multiples applied to earnings from the investment, analysis of recent comparable sales transactions, actual sale negotiations and bona fide purchase offers received from third parties, consideration of the amount that currently would be required to replace the asset, as adjusted for obsolescence, as well as independent external appraisals. In general, the Company considers several valuation techniques when measuring the fair value of a real estate investment. However, in certain circumstances, a single valuation technique may be appropriate. Real estate investments are reviewed on a quarterly basis by the Company for significant changes at the property level or a significant change in the overall market which would impact the value of the real estate investment resulting in unrealized appreciation or depreciation.

The Company also reflects its real estate equity investments net of investment level financing. Valuation adjustments attributable to underlying financing arrangements are considered in the

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

3. Significant Accounting Policies (Continued)

real estate equity valuation based on amounts at which the financing liabilities could be transferred to market participants at the measurement date.

Real estate and capital markets are cyclical in nature. Property and investment values are affected by, among other things, the availability of capital, occupancy rates, rental rates and interest and inflation rates. In addition, the Company invests in real estate and real estate related investments for which no liquid market exists. The market prices for such investments

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Significant Accounting Policies (Continued)

may be volatile and may not be readily ascertainable. Amounts ultimately realized by the Company from investments sold may differ from the fair values presented, and the differences could be material.

The Company's real estate investments are typically categorized as Level 3 within the fair value hierarchy as management uses significant unobservable inputs in determining their estimated fair value.

        See Note 45 and 56 for further information regarding the Company's investments, including equity method investments, and fair value measurements.

e.     Securities purchased under agreements to resell and securities sold under agreements to repurchase

        The Company uses securities purchased under agreements to resell and securities sold under agreements to repurchase ("Repurchase Agreements") as part of its liquidity management activities and to support its trading and risk management activities. In particular, securities purchased and sold under Repurchase Agreements are used for short-term liquidity purposes. As of June 30, 2011, Repurchase Agreements are secured predominantly by liquid corporate credit and/or government-issued securities. The use of Repurchase Agreements will fluctuate with the Company's need to fund short term credit or obtain competitive short term credit financing. The Company's securities purchased under agreements to resell and securities sold under agreements to repurchase were transacted pursuant to agreements with multiple counterparties as of June 30, 2011 and December 31, 2010.

Transactions involving purchases of securities under agreements to resell are carried at their contract value which approximates fair value. As of March 31,June 30, 2011 and December 31, 2010, the fair value of the collateral received by the Company was $70.3$76 million and $95.5 million, respectively.

        Transactions involving the sale of securities under agreements to repurchase are carried at their contract value and are accounted for as collateralized financings. In connection with these financings, as of March 31,June 30, 2011 and December 31, 2010, the Company had pledged collateral in the amount of $170$163.1 million and $207.4 million, respectively, which is included in securities owned, at fair value in the condensed consolidated statements of financial condition.

        Collateral is valued periodicallydaily and the Company and its counterparties may adjust the collateral or require additional collateral to be deposited when appropriate. Collateral held by counterparties may be sold or re-hypothecated by such counterparties, subject to certain limitations sometimes imposed by the Company. Collateralized repurchase agreementsRepurchase Agreements may result in credit exposure in the event the counterparties to the transactions are unable to fill their contractual obligations. The Company minimizes the credit risk associated with this activity by monitoring credit exposure and collateral

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

3. Significant Accounting Policies (Continued)

values, and by requiring additional collateral to be promptly deposited with or returned to the Company when deemed necessary. The Company's securities purchased under agreements

f.      Deferred rent

        Deferred rent primarily consists of step rent, allowances from landlords and fair valuing our leases property in accordance with GAAP in relation to resellbusiness combinations related to our leases properties. Step rent represents the difference between actual operating lease payments due and securities sold under agreementsstraight-line rent expense, which is recorded by the Company over the term of the lease, including the build-out period. This amount is recorded as deferred rent in the early years of the lease, when cash payments are generally lower than straight-line rent expense, and reduced in the later years of the lease when payments begin to repurchase were transacted pursuantexceed the straight-line expense. Landlord allowances are generally comprised of amounts received and/or promised to agreements with multiple counterparties at March 31,us by landlords and may be received in the form of cash or free rent. These allowances are part of the negotiated terms of the lease. We record a receivable from the landlord and a deferred rent liability when the allowances are earned. This deferred rent is amortized into income (through lower rent expense) over the term (including the pre-opening build-out period) of the applicable lease, and the receivable is reduced as amounts are received from the landlord. Liabilities resulting from valuing our leases acquired through business combinations are quantified by comparing the current fair value of the leases space to current rental payments. Deferred rent, included in a accounts payable, accrued expenses and other liabilities in the accompanying condensed consolidated statements of financial condition, for the years ended June 30, 2011 and December 31, 2010.2010 is $18.9 million and $15.1 million, respectively.

f.g.     Expenses

        Included within expenses infor the first quarter ofthree and six month ended June 30, 2011 is $2.8$0.7 million and $3.5 million, respectively, in acquisition-related expenses such as legal, consulting and banking fees, associated with the proposed acquisition of LaBranche & Co Inc. and other reorganization charges within the alternative investment management business.

g.h.     Recently adopted accounting pronouncements

        In June 2011, the FASB issued guidance which eliminates the current option to report other comprehensive income and its components in the statement of changes in equity. The guidance requires consecutive presentation of the statement of operation and other comprehensive income and present reclassification adjustments on the face of the financial statement from other comprehensive income to net income. This guidance helps financial statement users better understand the causes of an entity's change in financial position and results of operations. The guidance is effective retrospectively for interim and annual periods beginning after December 15, 2011. The Company is currently assessing the impact of this guidance on its condensed consolidated financial statements.

        In May 2011, the FASB issued guidance that changes the wording used to describe many of the requirements of GAAP for measuring the fair value and for disclosing information about fair value measurements. The guidance is effective prospectively for interim and annual periods beginning after December 15, 2011. Certain of the amendments could change how the fair value measurement guidance is applied including provisions related to highest and best use and valuation premise for

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

3. Significant Accounting Policies (Continued)

nonfinancial assets, application to financial assets and financial liabilities with offsetting positions in market risks or counterparty credit risk, premiums or discounts in fair value measurement, fair value of an instrument classified in a reporting entity's shareholders' equity, and additional disclosure requirements about fair value measurements. The Company is currently assessing the impact of this guidance on its condensed consolidated financial statements.

        In April 2011, the FASB issued guidance to improve the accounting for repurchase agreementsRepurchase Agreements (repos) and other agreements by modifying the criteria for determining when the transactions would be accounted for as financings (secured borrowings/lending agreements) as opposed to sales (purchases) with commitments to repurchase (resell). Specifically, the guidance removes from the assessment of effective control the criterion requiring the transferor to have the ability to repurchase or redeem the financial assets on substantially the agreed terms, even in default by the transferee. In accordance with

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Significant Accounting Policies (Continued)

the new guidance, the contractual rights and obligations determine effective control and there does not need to be a requirement to assess the ability to exercise those rights. The guidance is effective prospectively for new transfers and existing transactions that are modified in the first interim or annual period beginning on or after December 15, 2011. The Company is currently assessing the impact of this guidance on its condensed consolidated financial statements.

        In January 2010, the FASB issued guidance on improving disclosures about fair value measurements. The guidance requires additional disclosure on transfers in and out of Levels I1 and II2 fair value measurements in the fair value hierarchy and the reasons for such transfers. In addition, for fair value measurements using significant unobservable inputs (Level III)3), the reconciliation of beginning and ending balances shall be presented on a gross basis, with separate disclosure of gross purchases, sales, issuances and settlements and transfers in and transfers out of Level III.3. The new guidance also requires enhanced disclosures on the fair value hierarchy to disaggregate disclosures by each class of assets and liabilities. In addition, an entity is required to provide further disclosures on valuation techniques and inputs used to measure fair value for fair value measurements that fall in either Level II2 or Level III.3. The guidance is effective for interim and annual periods beginning after December 15, 2009, except for the disclosures about purchases, sales, issuances, and settlements in the roll forward of activity in Level III3 fair value measurements, which are effective for fiscal years beginning after December 15, 2010. The Company adopted the guidance, excluding the reconciliation of Level III3 activity, with the issuance of its March 31, 2010 financial statements. In addition, the Company first adopted the guidance related to the reconciliation of Level III3 activity in its March 31, 2011 condensed consolidation financial statements. As the guidance is limited to enhanced disclosures, adoption did not have a material impact on the Company's condensed consolidated financial statements.

        In March 2010, the FASB issued accounting guidance that changes the accounting for credit derivatives embedded in beneficial interests in securitized financial assets. The new guidance eliminates the scope exception for embedded credit derivatives, unless they are created solely by subordination of one financial instrument to another. Bifurcation and separate recognition may be required for certain beneficial interests that are currently not accounted for at fair value through earnings. The adoption of this accounting guidance on July 1, 2010 did not have a material impact on the Company's condensed consolidated financial statements.

        In April 2010, the FASB issued guidance on the accounting for stock awards to employees of a foreign operation or employees whose pay is denominated in a currency other than the one in which the equity security trades. The guidance clarifies that share-based payment awards with an exercise price denominated in the currency of a market in which a substantial portion of the entity's equity securities trade shall not be considered to contain a condition that is not a market, performance, or service condition. Such an award shall not be classified as a liability if it otherwise qualifies for equity classification. The guidance is effective for fiscal years and interim periods ending after December 15, 2010. The Company makes share-based payment awards to employees in foreign operations. The

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

3. Significant Accounting Policies (Continued)

guidance did not have a material impact on the Company's condensed consolidated financial statements.

        In December 2010, the FASB issued enhanced guidance on when to perform step two of the goodwill impairment test for reporting units with zero or negative carrying amounts. The updated guidance modifies existing requirements under step one of the goodwill impairment test for reporting

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

2. Significant Accounting Policies (Continued)

units with zero or negative carrying amounts and requires step two to be performed if it is more likely than not that a goodwill impairment exists. The guidance is effective for interim and annual reporting periods beginning after December 15, 2010. As the Company's reporting units do not currently have zero or negative carrying values, adoption isdid not expected to have a material impact on the Company's condensed consolidated financial statements.

        In December 2010, the FASB issued guidance on disclosures around business combinations for public entities that present comparative financial statements. The guidance specifies that an entity should disclose revenue and earnings of the combined entity as though the business combination(s) that occurred during the current year had occurred as of the beginning of the comparable prior annual reporting period. The guidance is effective prospectively for business combinations for which the acquisition date is on or after the beginning of the first annual reporting period beginning on or after December 15, 2010. As the guidance is limited to disclosures, adoption isdid not expected to have a material impact on the Company's condensed consolidated financial statements.

h.i.      Future adoption of accounting pronouncements

        As of March 31,June 30, 2011, none of the changes to the Codification issued by the FASB that are not yet effective are expected to have a material impact on the Company's financial position or results of operations.

3.4. Cash collateral pledged

        As of March 31,June 30, 2011 and December 31, 2010, cash collateral pledged in the amount of $9.8 million and $8.6 million, respectively, primarily relates to a) a bond held as collateral on a letter of credit and b) a letter of credit issued to the landlord of the Company's premises in New York City (see Note 13)14). Also included in cash collateral pledged as of March 31,June 30, 2011 and December 31, 2010 is $0.5 million, respectively, relating to an agreement that the Company has with Société Générale to cover the costs of litigation matters included in the agreement.

4.5. Investments of Operating Entities and Consolidated Funds

a.     Operating Entities

Securities owned, at fair value

        Securities owned are held by the Company and considered held for trading and carried at fair value. Substantially all equity securities and options are pledged to the clearing broker under terms which permit the clearing broker to sell or re-pledge the securities to others subject to certain limitations.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

4.5. Investments of Operating Entities and Consolidated Funds (Continued)

        As of March 31,June 30, 2011 and December 31, 2010, securities owned consisted of the following, at fair value:

        The Company's direct involvement with derivative financial instruments includes credit default swaps, futures, equity swaps, options and warrants and rights. Open equity in futures transactions are recorded as receivables from and payables to broker-dealers or clearing brokers as applicable. The Company's derivatives trading activities exposes us to certain risks, such as price and interest rate fluctuations, volatility risk, credit risk, foreign currency movements and changes in the liquidity of markets. The Company's long exposure to futures, equity swap and credit default swap derivative contracts, at fair value, as of March 31,June 30, 2011 and December 31, 2010 of $0.5 million and $0.4 million, respectively, is included in other assets in the accompanying condensed consolidated statements of financial condition. The Company's short exposure to futures and equity swap derivative contracts, at fair value, as of March 31,June 30, 2011 and December 31, 2010 of $0.8 million and $0.6 million, respectively, is included in accounts payable, accrued expenses and other liabilities in the accompanying condensed consolidated statements of financial condition.

The Company may transactgains/(losses) related to derivatives trading activities for the three months and six months ended June 30, 2011 were not material. The gains/(losses) on derivative contracts are included in a varietyother income in the condensed consolidated statements of derivative instruments primarily for trading purposes with each instruments' primary risk exposure being interest rate, credit, foreign exchange, equity or commodity risk.operations.

        Pursuant to the various derivatives transactions discussed above, the Company is required to post collateral for its obligations or potential obligations. As of March 31,June 30, 2011 and December 31, 2010, respectively, collateral consisting of $15.8 and $3.2 million, respectively, is included in receivable from brokers on the condensed consolidated statements of financial condition. As of March 31, 2011 and December 31, 2010 all derivative contracts were with major financial institutions.

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

4.5. Investments of Operating Entities and Consolidated Funds (Continued)

the condensed consolidated statements of financial condition. As of June 30, 2011 and December 31, 2010 all derivative contracts were with multiple major financial institutions.

Other investments

        As of March 31,June 30, 2011 and December 31, 2010, other investments consisted of the following:

Other investments

(1)    Portfolio Funds, at fair value

        The Portfolio Funds, at fair value as of March 31,June 30, 2011 and December 31, 2010, included the following:

Portfolio Funds, at fair value

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Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

4.5. Investments of Operating Entities and Consolidated Funds (Continued)

(2)    Real estate investments, at fair value

        Real estate investments as of March 31,June 30, 2011 and December 31, 2010 are carried at fair value and include real estate equity investments held by RCG RE Manager, LLC ("RE Manager"), a real estate operating subsidiary of the Company, of $1.4$1.5 million and $1.1 million, respectively, and real estate debt investments held by the Company of $0.8 million, respectively.

(3)    Equity method investments

        Equity method investments include investments held by the Company in several operating companies whose responsibilities primarily include the day to day management of a number of real estate funds, including the portfolio management and administrative services related to the acquisition, disposition, and active monitoring of the real estate funds' underlying debt and equity investments. The Company's ownership interests in these equity method investments range from 30% to 55%. The Company holds a majority of the outstanding ownership interest (i.e., more than 50%) in three of these entities: RCG Longview Debt Fund IV Management, LLC, RCG Longview Debt Fund IV Partners, LLC and RCG Longview Partners II, LLC. The operating agreements that govern the management of day-to-day operations and affairs of each of these three entities stipulate that certain decisions require support and approval from other members in addition to the support and approval of the Company. As a result, all operating decisions made in these three entities require the support of both the Company and an affirmative vote of a majority of the other managing members who are not affiliates of the Company that is not protective in nature. As the Company does not possess unilateral control over any of these entities, the presumption of consolidation has been overcome pursuant to current accounting standards and the Company accounts for these investments under the equity method of accounting. Also included in equity method investments is the investment in a) CHRP GP (see Note 3), b) an investment in the Chicago Board Options Exchange CBOE (Chicago Board Options

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Cowen Group, Inc.

Notes to Condensed Consolidated Financial Statements (Continued)

(unaudited)

4.5. Investments of Operating Entities and Consolidated Funds (Continued)

Exchange) Stock Exchange LLC representing a 9.7% stake in the exchange service provider and c)Starboard Value LP (and certain related parties) which serves as an operating company whose responsibilities primarily include the day to day management (including portfolio management) of accounting. Also included in equity method investments is the investment in CHRP GP (see Note 2).a deep value small cap hedge fund and related managed accounts. The following table summarizes equity method investments held by the Company: