PROSPECTUS SUPPLEMENT SUMMARY

PROSPECTUS SUPPLEMENT SUMMARY The summary contains basic information about us, the debentures and this offering. Because this is a summary, it does not contain all the information you should consider before investing in the debentures. You should carefully read this summary together with the more detailed infornunion, financial statements and notes to the financial statements contained elsewhere or incorporated by reference into this prospectus supplement or the accompanying prospectus. To fully understand this offering, you should read all of these documents. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus, on the other hand, the information in this prospectus supplement shall control. Unless otherwise indicated or the context otherwise requires, all references in this prospectus supplement and the accompanying prospectus to "W. R. Berkley." we. " "as. "our" or similar terms refer to W. R. Berkley Corporation. W. R. Berkley Corporation Introduction We are an insurance holding company that is among the largest commercial lines writers in the United States. We operate in the following segments of the property casualty insurance business: • insurance- primarily commercial insurance business, including excess and surplus lines and admitted lines, in the United States, the United Kingdom, Continental Europe, South America, Canada. Scandinavia. Asia and Australia; and • Reinsurance- reinsurance business on a facultative and treaty basis, primarily in the United States, the United Kingdom, Continental Europe. Australia, the Asia-Pacific Region, and South Africa. Each of our business segments is composed of individual operating units that serve a market defined by geography, products, services or types of customers. Each of our operating units is positioned close to its customer base and participates in a niche market requiring specialized knowledge about a territory or product. This strategy of decentralized operations allows each of our units to identify and respond quickly and effectively to changing market conditions and local customer needs, while capitalizing on the benefits of centralized capital. investment and reinsurance management, and corporate actuarial, financial, enterprise risk management and legal staff support. Our business approach is focused on meeting the needs of our customers, maintaining a high quality balance sheet, and allocating capital to our best opportunities. New businesses are started when opportunities are identified and when the right talent and expertise are found to lead a business. Our principal executive offices arc located at 475 Steamboat Road. Greenwich, Connecticut 06830, and our telephone number is (203) 629-3000. S-I EFTA_R1_02074078 EFTA02702272 The Offering Issuer W. R. Berkley Corporation Securities million aggregate principal amount of % Subordinated Debentures due 2056 ($ million aggregate principal amount if the underwriters exercise their overallotment option to purchase additional debentures in full). Maturity The debentures will mature on , 2056. Interest The debentures will bear interest at an annual rate of %. We will pay interest quarterly in arrears on and of each year, beginning on , 2016, subject to our right to defer the payment of interest as described under "Optional Interest Deferral" below. Record Date We will make interest payments on the debentures to the holders of record at the close of business on the or , as the case may be, immediately preceding such or , whether or not a business day. Ho• wever, inte• rest that we pay on the maturity date or redemption date will be payable to the person to whom the principal will be payable. Optional Interest Deferral We have the right on one or more occasions to defer the payment of interest on the debentures for up to five consecutive years (each such period. an "optional deferral period"). During an optional deferral period, interest will continue to accrue at the interest rate on the debentures, compounded quarterly as of each interest payment date to the extent permitted by applicable law. Payment Restrictions Upon Interest Deferral If we have exercised our right to defer interest payments on the debentures, we generally may not make payments on or redeem or purchase any shares of our capital stock or any of our debt securities or guarantees that rank equally with or junior to the debentures upon our liquidation, dissolution or winding up, subject to certain limited exceptions. Optional Redemption We may elect to redeem the debentures: • in whole at any time or in part from time to time on or after 2021, at a redemption price equal to their principal amount plus accrued and unpaid interest to. but excluding, the date of redemption: provided that if the debentures arc not redeemed in whole, at least $25 million aggregate principal amount of the debentures must remain outstanding after giving effect to such redemption: • in whole, but not in part, at any time prior to .2021, within 90 days of the occurrence of a "tax event" (as defined in S-2 EFTA_R1_02074079 EFTA02702273 "Description of Debentures —Optional Redemption of the Debentures") at a redemption price equal to their principal amount plus accrued and unpaid interest to, but excluding, the date of redemption; or • in whole, but not in part. at any time prior to . 2021. within 90 days of the occurrence of a "rating agency event" (as defined in "Description of Debentures —Optional Redemption of the Debentures") at a redemption price equal to the greater of (a) their principal amount or (b) a make-whole amount, in each case. plus any accrued and unpaid interest to, but excluding, the date of redemption. Subordination; Ranking The debentures will be unsecured, and will rank in right of payment and upon our liquidation junior to all of our existing and future Senior Indebtedness and will be par! prisms with Indebtedness Ranking on a Parity with the Debentures. The debentures will also be structurally subordinated to all liabilities of our subsidiaries. The debentures do not limit us or our subsidiaries' ability to incur additional debt, including debt that ranks senior in right of payment and upon our liquidation to the debentures. Events of Default The debentures can only be accelerated upon certain events of our bankruptcy. insolvency, or reorganization. See "Description of Debentures —Events of Default" below. Listing We intend to apply to list the debentures on the NYSE under the symbol "WRB PR D." If approved for listing, we expect trading of the debentures on the NYSE to commence within 30 days after they are first issued. Use of Proceeds We estimate that the net proceeds to us from this offering will be approximately S million (or approximately S million aggregate principal amount if the underwriters exercise their overallotment option to purchase additional debentures in full, assuming all retail sales) after deducting the underwriting discount and estimated offering expenses payable by us. We intend to use the net proceeds from this offering for general corporate purposes. See "Use of Proceeds" in this prospectus supplement. Risk Factors You should carefully consider all information set forth and incorporated by reference in this prospectus supplement and the accompanying prospectus and, in particular, you should carefully read the section entitled "Risk Factors" in this prospectus supplement and the accompanying prospectus and the section entitled "Item IA. Risk Factors" of our Annual Report on Form 10-K for the year ended December 31, 2015 before purchasing any of the debentures. Trustee The Bank of New York Mellon. Governing Law The debentures will be governed by the laws of the State of New York. S-3 EFTA_R1_02074080 EFTA02702274 RISK FACTORS Before you invest in the debentures, you should carefully consider the risks involved. Accordingly, you should carefully, consider the information contained in or incorporated by reference into this prospectus supplement and the accompanying prospectus, including the risk factors listed below and in our Annual Report on Form 10 -K for the year ended December 31,2015 and in the other documents incorporated by reference in this prospectus supplement. Our substantial indebtedness could adversely affect our financial health and prevent us from fulfilling our obligations under the debentures. We have now and, after the offering, will continue to have a significant amount of indebtedness. On March 31, 2016. before giving effect to this offering, we had total indebtedness of approximately $2.3 billion, including our existing subordinated debentures. We may incur additional indebtedness that may adversely affect our ability to meet our financial obligations under the debentures. The terms of the indenture and the debentures do not impose any limitation on our or our subsidiaries' ability to incur additional debt. We may incur additional indebtedness in the future, which could have important consequences to holders of the debentures, including the following: • we could have insufficient cash to meet our financial obligations, including our obligations under the debentures; • our ability to obtain additional financing for working capital. capital expenditures or general corporate purposes may be impaired; and • a significant degree of debt could make us more vulnerable to changes in general economic conditions and also could affect the financial strength ratings of our insurance subsidiaries. We are an insurance holding company and, therefore, may not be able to receive dividends in amounts needed to service our debt. As an insurance holding company, our principal assets are the shares of capital stock of our insurance company subsidiaries. We have to rely on dividends from our insurance company subsidiaries to meet our obligations for paying principal and interest on outstanding debt obligations and for paying corporate expenses. The payment of dividends by our insurance company subsidiaries is subject to regulatory restrictions and will depend on the surplus and future earnings of these subsidiaries, as well as the regulatory restrictions. For 2016. the maximum amount of dividends that can be paid without regulatory approval is approximately $684 million, of which approximately $584 million has been paid to date. As a result, we may not be able to receive dividends from these subsidiaries at times and in amounts necessary to meet our obligations under the debentures. Our obligations under the debentures will be subordinated. Our payment obligation under the debentures will be unsecured and will rank junior in right of payment and upon our liquidation to all of our Senior Indebtedness on the terms set forth in the indenture pursuant to which the debentures will be issued. We, therefore, cannot make any payments on the debentures, if (i) we have defaulted on the payment of any of our Senior Indebtedness and the default is continuing, (ii) the maturity of any Senior Indebtedness has been or would be permitted upon notice or the passage of time to be accelerated as a result of a default and the default is continuing and such acceleration has not been rescinded or annulled or (iii) we have filed for bankruptcy or are liquidating, dissolving or winding-up or in receivership, and our Senior Indebtedness has not been repaid in full. S-4 EFTA_R1_02074081 EFTA02702275 As of March 31, 2016, we had approximately $1,828 million in outstanding Senior Indebtedness and $460 million of Indebtedness Ranking on a Parity with the Debentures. The indenture pursuant to which the debentures will be issued does not place any limit on the amount of liabilities that we may issue. guarantee or otherwise incur or the amount of liabilities, including debt or preferred stock, that our subsidiaries may issue, guarantee or otherwise incur. We expect from time to time to incur additional indebtedness and other liabilities and to guarantee indebtedness that will be senior to the debentures. The debentures will be effectively subordinated to the liabilities of our subsidiaries. We have limited operations of our own and derive substantially all of our revenue and cash flow from our subsidiaries. None of our subsidiaries will guarantee the debentures. Creditors of our subsidiaries (including policyholders and trade creditors) will generally be entitled to payment from the assets of those subsidiaries before those assets can be distributed to us. As a result, the debentures will effectively be subordinated to the liabilities of our subsidiaries. As of March 31. 2016. our subsidiaries had approximately $61 million in outstanding debt and our insurance subsidiaries had gross reserves for losses and loss expenses of approximately $10.8 billion. We can defer interest payments on the debentures for one or more periods of up to five years each. This may affect the market price of the debentures. So lung as there is no event of default with respect to the debentures, we may defer interest payments on the debentures, from time to time, for one or more optional deferral periods of up to five consecutive years. At the end of an optional deferral period, if all amounts due are paid. we could start a new optional deferral period of up to five consecutive years. During any optional deferral period, interest on the debentures would be deferred but would accrue additional interest at a rate equal to the interest rate on the debentures, to the extent permitted by applicable law. No optional deferral period may extend beyond the maturity date of the debentures. See "Description of Debentures —Option to Defer Interest Payments." If we exercise our right to defer interest payments, the debentures may trade at a price that does not fully reflect the value of accrued and unpaid interest on the debentures or that is otherwise less than the price at which the debentures may have been traded if we had not exercised such right. ►n addition, as a result of our right to defer interest payments, the market price of the debentures is likely to be affected and may be more volatile than other securities that do not have these rights. If we do defer interest on the debentures and you sell your debentures during the period of that deferral, you may not receive the same return on your investment as a holder that continues to hold its debentures until we pay the deferred interest at the end of the applicable deferral period. A holder of the debentures will not have rights of acceleration in the case of payment defaults or other breaches of covenants. The only event of default under the indenture consists of specific events of our bankruptcy. insolvency or receivership. There is no right of acceleration in the case of payment defaults or other breaches of covenants under the indenture. If we defer interest payments on the debentures, there will be U.S. federal income tax consequences to holders of the debentures. If we were to defer interest payments on the debentures, the debentures would be treated as issued with original issue discount ("OID") at the time of such deferral, and all stated interest due after such deferral would be treated as OID. In such case, a United States holder would be required to include such stated interest in income as it accrues, regardless of such United States holder's regular method of accounting. using a constant yield method, before such holder received any payment attributable to such income, and would not separately report the actual payments of interest on the debentures as taxable income. S-5 EFTA_R1_02074082 EFTA02702276 If holders of the debentures sell their debentures before the record date for the payment of interest at the end of an optional deferral period, they will not receive such interest. Instead, the accrued interest will be paid to the holder of record on the record date regardless of who the holder of record may have been on any other date during the optional deferral period. Moreover, amounts that holders were required to include in income in respect of the debentures during the optional deferral period will be added to such holders' adjusted tax basis in the debentures, but may not be reflected in the amount that such holder realizes on the sale. To the extent the amount realized on a sale is less than the holder's adjusted tax basis, the holder will generally recognize a capital loss for U.S. federal income tax purposes. The deductibility of capital losses is subject to limitations. See "Material United States Federal Income Tax Considerations —Sale, Exchange, Redemption or Other Disposition of Debentures." Rating agencies may change their practices for rating the debentures, which change may affect the market price of the debentures. In addition, we may redeem the debentures if a rating agency amends, clarifies or changes the criteria used to assign equity credit for securities similar to the debentures. The rating agencies that currently publish a rating for us, including Moody's Investors Service, Inc., Standard & Poor's Ratings Services, a Standard & Poor's Financial Services LLC business, and A.M. Best Company, Inc., may, from time to time in the future, change the way they analyze securities with features similar to the debentures. This may include, for example, changes to the relationship between ratings assigned to an issuer's senior securities and ratings assigned to securities with features similar to the debentures. If the rating agencies change their practices for rating these types of securities in the future, and the ratings of the debentures are subsequently lowered, that could have a negative impact on the trading price of the debentures. In addition, we may redeem the debentures before 2021 at our option, in whole, but not in part, within 90 days of a rating agency amending, clarifying or changing the criteria used to assign equity credit for securities such as the debentures, which amendment, clarification or change results in (i) the shortening of the length of time the debentures are assigned a particular level of equity credit by that rating agency as compared to the length of time they would have been assigned that level of equity credit by that rating agency or its predecessor on the initial issuance of the debentures: or (ii) the lowering of the equity credit (including up to a lesser amount) assigned to the debentures by that rating agency compared to the equity credit assigned by that rating agency or its predecessor on the initial issuance of the debentures. See "Description of Debentures —Optional Redemption of the Debentures." The debentures may be redeemed prior to maturity, and you may not be able to reinvest the proceeds at the same or a higher rate. We may redeem the debentures at our option, in whole at any time or in part, on or after .2021. In addition, we may redeem the debentures in whole, but not in pan, before . 2021 if certain changes in tax laws, regulations or interpretations occur. In each of these two cases, the redemption price will be 100% of the principal amount of such debentures being redeemed plus accrued and unpaid interest to. but excluding, the date of redemption. We may also redeem the debentures before , 2021 at our option, in whole, but not in part, within 90 days of a "rating agency event- (as defined in "Description of Debentures —Optional Redemption of the Debentures"). In this event, the redemption price will be equal to the greater of (i) the aggregate principal amount or (ii) a make-whole amount, in each case, plus accrued and unpaid interest to. but excluding, the date of redemption. See "Description of Debentures —Optional Redemption of the Debentures." If we exercise any of these rights. you may not be able to reinvest the money you receive upon a redemption at a rate that is equal to or higher than the rate of return on the debentures. There may not be a public market for the debentures. We will apply to list the debentures on the NYSE under the symbol "WRB PR D." If approved for listing. we expect trading of the debentures on the NYSE to commence within 30 days after they are first issued. The listing of the debentures will not necessarily ensure that an active trading market will be available for the S-6 EFTA_R1_02074083 EFTA02702277 debentures or that you will be able to sell your debentures at the price you originally paid for them or at the time you wish to sell them. Future trading prices of the debentures will depend on many factors including, among other things, prevailing interest rates, our operating results and the market for similar securities. Generally, the liquidity of, and trading market for, the debentures may also be materially and adversely affected by declines in the market for similar debt securities. Such a decline may materially and adversely affect such liquidity and trading independent of our financial performance and prospects. Changes in our credit ratings or the debt markets could adversely affect the market price of the debentures. The market price for the debentures depends on many factors, including, among other things: • our credit ratings with major credit rating agencies, including with respect to the debentures; • the prevailing interest rates being paid by other companies similar to us; • our operating results, financial condition, financial performance and future prospects; • our election to defer interest payments on the debentures (see—"We can defer interest payments on the debentures for one or more periods of up to five years each. This may affect the market price of the debentures."); and • economic, financial, geopolitical, regulatory and judicial events that affect us, the industries and markets in which we are doing business and the financial markets generally, including continuing market volatility and uncertainty about the U.S. economy and other key economies, and sovereign credit and bank solvency concerns in Europe and other key economies. The price of the debentures may be adversely affected by unfavorable changes in these factors. The condition of the financial markets and prevailing interest rates have fluctuated in the past and are likely to fluctuate in the future. Such fluctuations could have an adverse effect on the price of the debentures. In addition, credit rating agencies continually review their ratings for the companies that they follow. including us. The credit rating agencies also evaluate the insurance industry as a whole and may change our credit rating based on their overall view of our industry. A negative change in our rating could have an adverse effect on the price of the debentures. S-7 EFTA_R1_02074084 EFTA02702278 FORWARD -LOOKING STATEMENTS This prospectus supplement and the accompanying prospectus and those documents incorporated by reference herein and therein may contain certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Some of the forward-looking statements can be identified by the use of forward-looking words such as •believes." "expects." "potential," "continued." "may." "will" "should." "seeks," "approximately." "predicts," "intends," "plans." "estimates." "anticipates" or the negative version of those words or other comparable words. Any forward-looking statements contained or incorporated by reference in this prospectus supplement and the accompanying prospectus, including statements related to our outlook for the industry and for our performance for the year 2016 and beyond. are based upon our historical performance and on current plans, estimates and expectations. The inclusion of this forward-looking information should not be regarded as a representation by us, the underwriters or any other person that the future plans, estimates or expectations contemplated by us will be achieved. Such forward-looking statements are subject to various risks and uncertainties, including but not limited to: • the cyclical nature of the property casualty industry; • the impact of significant competition including new alternative entrants to the industry: • the long-tail and potentially volatile nature of the insurance and reinsurance business: • product demand and pricing; • claims development and the process of estimating reserves: • investment risks, including those of our portfolio of fixed maturity securities and investments in equity securities, including investments in financial institutions, municipal bonds, mortgage-backed securities, loans receivable, investment funds, real estate, merger arbitrage, energy related and private equity investments; • the effects of emerging claim and coverage issues: • the uncertain nature of damage theories and loss amounts; • natural and man-made catastrophic losses, including as a result of terrorist activities; • general economic and market activities, including inflation, interest rates and volatility in the credit and capital markets; • the impact of the conditions in the financial markets and the global economy, and the potential effect of legislative, regulatory, accounting or other initiatives taken in response to it, on our results and financial condition: • foreign currency and political risks relating to our international operations; • our ability to attract and retain key personnel and qualified employees: • continued availability of capital and financing; • the success of our new ventures or acquisitions and the availability of other opportunities: • the availability of reinsurance; • our retention under the Terrorism Risk Insurance Program Reauthorization Act of 2015; • the ability or willingness of our reinsurers to pay reinsurance recoverables owed to us: • other legislative and regulatory developments, including those related to business practices in the insurance industry; • credit risk relating to our policyholders, independent agents and brokers; • changes in the ratings assigned to us or our insurance company subsidiaries by rating agencies: S-8 EFTA_R1_02074085 EFTA02702279 the availability of dividends from our insurance company subsidiaries: potential difficulties with technology and/or data security; the effectiveness of our controls to ensure compliance with guidelines, policies and legal and regulatory standards; and • other risks detailed in our Annual Report on Form 10-K for the year ended December 31, 2015 and from time to time in our other filings with the Securities and Exchange Commission ("SEC"). We describe some of these risks and uncertainties in greater detail under the caption "Risk Factors" above, beginning on page 6 of the accompanying prospectus and in our Annual Report on Form 10-K for the year ended December 31, 2015, which is incorporated herein by reference. These risks and uncertainties could cause our actual results for the year 2016 and beyond to differ materially from those expressed in any forward-looking statement we make. Any projections of growth in our revenues would not necessarily result in commensurate levels of earnings. Our future financial performance is dependent upon factors discussed elsewhere in this prospectus supplement and the accompanying prospectus and the documents incorporated by reference herein and therein. Forward-looking statements speak only as of the date on which they are made. Our filings with the SEC, which discuss these risks and uncertainties, are described below under the captions "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference." USE OF PROCEEDS We estimate that the net proceeds to us from this offering will be approximately $ million (or approximately $ million aggregate principal amount if the underwriters exercise their overallotment option to purchase additional debentures in full, assuming all retail sales) after deducting the underwriting discount and estimated offering expenses payable by us. We intend to use the net proceeds from this offering for general corporate purposes. S-9 EFTA_R1_02074086 EFTA02702280 CAPITALIZATION The following table shows our capitalization at March 31, 2016 and as adjusted to give effect to the debentures offered by this prospectus supplement (assuming no exercise of the underwriters' overallotment option to purchase additional debentures). You should read this table in conjunction with our historical consolidated financial statements and the other financial and statistical information that are included or incorporated by reference in this prospectus supplement and the accompanying prospectus. Debt: % Subordinated Debentures due 2056 As of March 31.2016 I In thousands. except percentage data) Actual As Adjusted S — S Other subordinated debentures 446.485 446.485 Other debt 1,814.998 1.814.998 Total debt 2,261.483 Equity: Preferred stock, par value $0.10 per share: No shares issued Common stock, par value 50.20 per share 47.024 47,024 Additional paid-in capital 1,013.572 1,013,572 Retained earnings 6,282.870 6,282,870 Accumulated other comprehensive income (loss) 8.124 8,124 Treasury stock, at cost (2,600,377) (2,600,377) Total stockholders' equity 4,751,213 4,751,213 Noncontrolling interests 36.843 36.843 Total equity 4,788,056 4,788,056 Total capitalization S 7.049,539 S Ratios: Total debt to total capitalization 32.1% RATIO OF EARNINGS TO FIXED CHARGES The following table sets forth our ratio of earnings to fixed charges for the periods indicated. For purposes of the computation of ratio of earnings to fixed charges. earnings consist of income before income taxes. change in accounting and extraordinary items plus fixed charges. Fixed charges consist of interest expense, plus capitalized interest, amortization of financing costs and one-third of minimum rental payments under operating leases. The ratios set forth below do not reflect the issuance of the debentures. Three Months Ended Year Ended December 31. Mardi 31, 2016 2015 2014 2013 2012 2011 Ratio of earnings to fixed charges 5.8 6.0 7.6 6.0 6.0 5.2 S-I0 EFTA_R1_02074087 EFTA02702281 DESCRIPTION OF DEBENTURES Set forth below is a description of the specific terms of the debentures. This description supplements, and should be read together with, the description of the general terms and provisions of our debt securities set forth in the accompanying prospectus under the caption "Description of the Debt Securities." Any infonnotion regarding tire debentures contained in this prospectus supplement that is inconsistent with information in the accompanying prospectus will supersede any inconsistent information in the accompanying prospectus. The following description does not purport to be complete and is subject to, and qualified in its entirety by reference to, the subordinated indenture, as supplemented by the second supplemental indenture, to provide for the issuance of the debentures which we collectively refer to as the "indenture." between W. R. Berkley Corporation, as issuer, and The Bank of New York Mellon, as trustee, which we refer to as the "trustee." pursuant to which the debentures will be issued. General The debentures will be issued as subordinated debt securities under the indenture and will be limited in aggregate principal amount to S (S aggregate principal amount if the underwriters exercise their overallotment option to purchase additional debentures in full). The debentures will be issued only in denominations of S25 and multiples of 525 in excess thereof. Payments of principal of. and interest on, the debentures will be made in U.S. dollars. The provisions of the indenture pertaining to satisfaction and discharge of the indenture. defeasance. covenant defeasance and unclaimed moneys will apply to the debentures. We may, without notice to or consent of the holders of the debentures, re-open and issue additional % Subordinated Debentures due 2056 having the same ranking, interest rate, maturity date and other terms as the debentures of such series being offered by this prospectus supplement, provided that the additional debentures arc fungible with the debentures being offered in this prospectus supplement for United States federal income tax purposes. Any additional debentures, together with the debentures offered by this prospectus supplement, will constitute a single series of debt securities under the indenture. The debentures and the indenture under which the debentures will be issued do not place any limitation on the amount of unsecured debt that may be incurred by us. Subordination The debentures will be unsecured, and will rank in right of payment and upon our liquidation junior to all of our current and future Senior Indebtedness and purl passu with our outstanding 5.625% Subordinated Debentures due 2053, our outstanding 5.900% Subordinated Debentures due 2056 and any other future Indebtedness Ranking on a Parity with the Debentures, and, in each case in the manner set forth below. The debentures will also be structurally subordinated to all debt and other liabilities of our subsidiaries. Upon any payment or distribution of assets to creditors upon any receivership, liquidation, dissolution. winding up. reorganization. assignment for the benefit of creditors. marshaling of assets or any bankruptcy, insolvency, or similar proceedings. the holders of Senior Indebtedness will first be entitled to receive payment in full in cash or other satisfactory consideration of all amounts due or to become due on or in respect of such Senior Indebtedness before the holders of the debentures will be entitled to receive or retain any payment in respect thereof. In the event of the acceleration of the maturity of the debentures, the holders of all Senior Indebtedness outstanding at the time of such acceleration will first be entitled to receive payment in full in cash or other satisfactory consideration of all such Senior Indebtedness before the holders of the debentures will be entitled to receive or retain any payment in respect of the debentures. In the event and during the continuation of any default in any payment with respect to any Senior Indebtedness, or in the event that the maturity of any Senior Indebtedness has been or would be permitted upon notice or the passage of time to be accelerated because of a default, then, unless and until such default shall have S-II EFTA_R1_02074088 EFTA02702282 been cured or waived or shall have ceased to exist and such acceleration shall have been rescinded or annulled, then no payments on account of principal or premium, if any, or interest or additional amounts, if any, in respect of the debentures may be made, in each case unless and until all amounts due or to become due on such Senior Indebtedness are paid in full in cash or other satisfactory consideration. As at March 31, 2016. we had approximately $1,828 million of outstanding Senior Indebtedness and $460 million of Indebtedness Ranking on a Parity with the Debentures. In addition, the debentures will be structurally subordinate to all liabilities of our subsidiaries. As of March 31, 2016, our subsidiaries had approximately $61 million in outstanding debt and our insurance subsidiaries had gross reserves for losses and loss expenses of approximately $10.8 billion. See "Risk Factors—The debentures will be effectively subordinated to the debts of our subsidiaries." Senior Indebtedness does not include obligations to trade creditors created or assumed by us in the ordinary course of business, which will rank pail passu with the debentures in right of payment upon liquidation. "Senior Indebtedness" shall mean all Indebtedness, whether outstanding on the date of the first issuance of the debentures or thereafter created, assumed or incurred, except Indebtedness Ranking on a Parity with the Debentures or Indebtedness Ranking Junior to the Debentures, and any deferrals, renewals or extensions of such Senior Indebtedness. "Indebtedness Ranking on a Parity with the Debentures" shall mean (a) our outstanding 5.625% Subordinated Debentures due 2053, (b) our outstanding 5.900% Subordinated Debentures due 2056 and (c) Indebtedness, whether outstanding on the date of the first issuance of the debentures or thereafter created, assumed or incurred, which specifically by its terms ranks equally with and not prior to the debentures in right of payment upon our dissolution, winding-up, liquidation, reorganization or similar events. The securing of any Indebtedness, otherwise constituting Indebtedness Ranking on a Parity with the Debentures, shall not be deemed to prevent such Indebtedness from constituting Indebtedness Ranking on a Parity with the Debentures. "Indebtedness Ranking Junior to the Debentures" shall mean any Indebtedness, whether outstanding on the date of the first issuance of the debentures or thereafter created, assumed or incurred, which specifically by its terms ranks junior to and not equally with or prior to the debentures (and any Indebtedness Ranking on a Parity with the Debentures) in right of payment upon our dissolution, winding-up, liquidation. reorganization. or similar events. The securing of any Indebtedness, otherwise constituting Indebtedness Ranking Junior to the Debentures, shall not be deemed to prevent such Indebtedness from constituting Indebtedness Ranking Junior to the Debentures. "Indebtedness" shall mean (a) any obligation of. or any obligation guaranteed by. us for which we are responsible or liable as obligor or otherwise including principal, premium and interest (whether accruing before or after filing of any petition in bankruptcy or any similar proceedings by or against us and whether or not allowed as a claim in bankruptcy or similar proceedings) for (i) indebtedness for money borrowed. (ii) indebtedness evidenced by securities, bonds, debentures. notes or other similar written instruments, (iii) any deferred obligation for the payment of the purchase price or conditional sale obligation of property or assets acquired other than in the ordinary course of business, (iv) all obligations for the reimbursement of any letter of credit, banker's acceptance. security purchase facility or similar credit transaction. (v) all obligations under "keep-well" agreements required by insurance regulators or (vi) any obligation referred to in (i) through (v) above of other persons secured by any lien on any property or asset of the Company and (b) all indebtedness for obligations to make payment in respect of derivative products such as interest and foreign exchange rate contracts, commodity contracts (including future or options contracts) swap agreements. cap agreements, repurchase and reverse repurchase agreements and similar arrangements, whether outstanding on the first issuance of the debentures or thereafter created, assumed or incurred. Maturity The debentures will mature on . 2056. S-12 EFTA_R1_02074089 EFTA02702283 Interest Subject to applicable law and subject to any optional deferral period, as described below, interest on the debentures will accrue at an annual rate equal to %, and will be payable quarterly in arrears on and of each year. beginning on 2016, each of which we refer to as an interest payment date, to the record holders at the close of business on the preceding and , as applicable, whether or not a business day. However, interest that we pay on the maturity date or a redemption date will be payable to the person to whom the principal will be payable. Interest payments will include accrued interest from, and including, the original issue date, or, if interest has already been paid, from the last date in respect of which interest has been paid or duly provided for to, but excluding, the next succeeding interest payment date, the maturity date or the redemption date, as the case may be. The amount of interest payable for any interest payment period will be computed on the basis of a 360-day year comprised of twelve 30-day months. If any date on which interest is payable on the debentures is not a business day, then payment of the interest payable on such date will be made on the next succeeding day that is a business day (and without any interest or other payment in respect of any such delay). Interest not paid on any payment date will accrue and compound quarterly at a rate per year equal to the rate of interest on the debentures until paid. References to "interest" include interest accruing on the debentures. interest on deferred interest payments and other unpaid amounts and compounded interest, as applicable and in each case to the extent permitted by applicable law. Option to Defer Interest Payments So long as no event of default with respect to the debentures has occurred and is continuing, we may. on one or more occasions, defer interest payments on the debentures for one or more optional deferral periods of up to five consecutive years without giving rise to an event of default under the terms of the debentures. A deferral of interest payments cannot extend, however, beyond the maturity date or the earlier acceleration or redemption of the debentures. During an optional deferral period, interest will continue to accrue on the debentures, and deferred interest payments will accrue additional interest at the same rate, compounded quarterly as of each interest payment date to the extent permitted by applicable law. During an optional deferral period, we will be prohibited from paying current interest on the debentures until we have paid all accrued and unpaid deferred interest plus any accrued interest thereon. No interest otherwise due during an optional deferral period will be due and payable on the debentures until the end of such optional deferral period except upon an acceleration or redemption of the debentures during such deferral period. At the end of five years following the commencement of an optional deferral period, we must pay all accrued and unpaid deferred interest, including compounded interest. If, at the end of any optional deferral period, we have paid all deferred interest due on the debentures, including compounded interest, we can again defer interest payments on the debentures as described above. We will provide to the trustee and the holders of debentures written notice of any deferral of interest at least one and not more than 60 business days prior to the applicable interest payment date. We have no present intention of exercising our right to defer payments of interest. Payment Restrictions During a Deferral Period After the commencement of an optional deferral period until we have paid all accrued and unpaid interest on the debentures, we will not, and will not permit any of our subsidiaries to: • declare or pay any dividends or distributions on. or redeem, purchase, acquire, or make a liquidation payment with respect to, any of our capital stock (which includes common and preferred stock): 5-13 EFTA_R1_02074090 EFTA02702284 • make any payment of principal. interest or premium on or repay, repurchase or redeem any Indebtedness Ranking on a Parity with the Debentures or Indebtedness Ranking Junior to the Debentures; or • make any guarantee payments with respect to any guarantee by us of any securities of any of our subsidiaries if such guarantee ranks pail passe with or junior in right of payment to the debentures; other than: • dividends or distributions in shares of, or options. warrants or rights to subscribe for or purchase shares of. our capital stock where the dividend stock or stock issuable upon exercise of such options, warrants or other rights is the same stock as that on which the dividend is being paid or ranks equally with or junior to such stock: • any declaration of a dividend in connection with the implementation of a stockholder's rights plan, or the issuance of capital stock under any such plan in the future, or the redemption or repurchase of any such rights pursuant thereto: • as a result of a reclassification of any series or class of our capital stock or the exchange or conversion of one class or series of our capital stock for or into another class or series of our capital stock: • the purchase of fractional interests in shares of our capital stock pursuant to an acquisition or the conversion or exchange provisions of such capital stock or the security being converted or exchanged; • purchases or acquisitions of shares of our capital stock in connection with any employment contract. benefit plan or other similar arrangement with or for the benefit of directors, officers, agents, consultants or employees or our satisfaction of our obligations under any dividend reinvestment plan or our director, officer, agent. consultant or employee stock purchase plans: • any exchange, redemption or conversion of any class or series of our capital stock, or the capital stock of one of our subsidiaries, for any other class or series of our capital stock, or of any class or series of our Indebtedness for any class or series of our capital stock; • purchases or acquisitions of shares of our capital stock in connection with our satisfaction of our obligations under any contract or security entered into before commencement of the optional deferral period; and • (i) payment of current or deferred interest on our Indebtedness Ranking on a Parity with the Debentures made pro rata to the amounts due on our Indebtedness Ranking on a Parity with the Debentures and the debentures and (ii) payment of principal or current or deferred interest on our Indebtedness Ranking on a Parity with the Debentures that, if not made, would cause us to breach the terms of the instrument governing such Indebtedness Ranking on a Parity with the Debentures. Optional Redemption of the Debentures We may redeem the debentures in increments of S25 principal amount: • in whole at any time or in part from time to time on or after , 2021. at a redemption price equal to their principal amount plus accrued and unpaid interest (including compounded interest, if any) to. but excluding, the date of redemption; provided that if the debentures am not redeemed in whole, at least S25 million aggregate principal amount of the debentures must remain outstanding after giving effect to such redemption; • in whole, but not in part, at any time prior to 2021. within 90 days of the occurrence of a "tax event: at a redemption price equal to their principal amount plus accrued and unpaid interest (including compounded interest, if any) to. but excluding, the date of redemption; or S-I4 EFTA_R1_02074091 EFTA02702285 • in whole, but not in part, at any time prior to , 2021, within 90 days of the occurrence of a "rating agency event," at a redemption price equal to the greater of (a) 100% of their principal amount or (b) the present value of a payment on , 2021 in an amount equal to their outstanding principal amount and scheduled payments of interest that would have accrued from the date of redemption to , 2021 on the debentures, discounted to the date of redemption on a quarterly basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus basis points, in each case, plus any accrued and unpaid interest (including compounded interest, if any) to but excluding the date of redemption. "Tax event" means that we will have received an opinion of counsel, rendered by a law firm of nationally recognized standing that is experienced in such matters, stating that, as a result of any: • amendment to. or change in (including any promulgation, enactment, execution or modification on the laws (or any regulations under those laws) of the United States or any political subdivision thereof or therein affecting taxation: • official administrative pronouncement (including a private letter ruling, technical advice memorandum or similar pronouncement) or judicial decision or administrative action or other official pronouncement interpreting or applying the laws or regulations enumerated in the preceding bullet point, by any court, governmental agcncy or regulatory authority; or • threatened challenge asserted in connection with an audit of us, or a threatened challenge asserted in writing against any taxpayer that has raised capital through the issuance of securities that are substantially similar to the debentures. which amendment or change is enacted or effective or which pronouncement or decision is announced or which challenge is asserted against us or becomes publicly known on or after the original issue date of the debentures, there is more than an insubstantial increase in the risk that interest accruable or payable by us on the debentures is not, or will not be, deductible by us in whole or in part, for U. S. federal income tax purposes. "Rating agency event" means that any nationally recognized statistical rating organization within the meaning of Section 3(aX62) under the Securities Exchange Act of 1934. as amended (the "Exchange Act-), that then publishes a rating for us (a "rating agency") amends, clarifies or changes the criteria it uses to assign equity credit to securities such as the debentures, which amendment, clarification or change results in (a) the shortening of the length of time the debentures are assigned a particular level of equity credit by that rating agency as compared to the l