x   ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF

For the fiscal year ended December 31, 2017

o  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF

For the transition period from to

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Act. Yes x No o

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o No x

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 x  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 x  No o

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. 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, as defined in Rule 12b-2 of the Act. Large accelerated filer x, Accelerated filer o, Non-accelerated filer o, Smaller reporting company o, Emerging growth company o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

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

The aggregate market value of Common Shares held by nonaffiliates of the registrant at June 30, 2017 was $5,498.0 million based on the closing sale price of the Common Shares on the New York Stock Exchange on that date.

The number of Common Shares, par value US $1.00 per share, outstanding at February 2, 2018 was 40,023,789.

Portions of the registrant’s definitive proxy statement for the 2018 Annual General Meeting of Shareholders are incorporated by reference into Part III of this report.

This Annual Report on Form 10-K for the year ended December 31, 2017 (this “Form 10-K”) of RenaissanceRe Holdings Ltd. (“RenaissanceRe”) contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Forward-looking statements are necessarily based on estimates and assumptions that are inherently subject to significant business, economic and competitive uncertainties and contingencies, many of which, with respect to future business decisions, are subject to change. These uncertainties and contingencies can affect actual results and could cause actual results to differ materially from those expressed in any forward-looking statements made by, or on behalf of, us. In particular, statements using words such as “may”, “should”, “estimate”, “expect”, “anticipate”, “intend”, “believe”, “predict”, “potential”, or words of similar import generally involve forward-looking statements. For example, we may include certain forward-looking statements in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” with regard to trends in results, prices, volumes, operations, investment results, margins, combined ratios, fees, reserves, market conditions, risk management and exchange rates. This Form 10-K also contains forward-looking statements with respect to our business and industry, such as those relating to our strategy and management objectives, market standing and product volumes, competition and new entrants in our industry, industry capital, insured losses from loss events, government initiatives and regulatory matters affecting the reinsurance and insurance industries.

We aspire to be the world’s best underwriter by matching well-structured risks with efficient sources of capital and our mission is to produce superior returns for our shareholders over the long term. We seek to accomplish these goals by being a trusted, long-term partner to our customers for assessing and managing risk, delivering responsive and innovative solutions, leveraging our core capabilities of risk assessment and information management, investing in these core capabilities in order to serve our customers across the cycles that have historically characterized our markets and keeping our promises. Our strategy focuses on superior risk selection, superior customer relationships and superior capital management. We provide value to our customers and joint venture partners in the form of financial security, innovative products, and responsive service. We are known as a leader in paying valid claims promptly. We principally measure our financial success through long-term growth in tangible book value per common share plus the change in accumulated dividends, which we believe is the most appropriate measure of our financial performance and in respect of which we believe we have delivered superior performance over time.

Superior Customer Relationships. We seek to be a trusted long-term partner to our customers for assessing and managing risk and delivering responsive solutions. We believe our modeling and technical expertise, our risk management products and our track record of keeping our promises have made us a provider of first choice in many lines of business to our customers worldwide. We seek to offer stable, predictable and consistent risk-based pricing and a prompt turnaround on claims.

Superior Risk Selection. We seek to build a portfolio of risks that produces an attractive risk-adjusted return on utilized capital. We develop a perspective of each risk using both our underwriters’ expertise and sophisticated risk selection techniques, including computer models and databases such as Renaissance Exposure Management System (“REMS©”). We pursue a disciplined approach to underwriting and seek to select only those risks that we believe will produce a portfolio with an attractive return, subject to prudent risk constraints. We manage our portfolio of risks dynamically, both within sub-portfolios and across the Company.

Superior Capital Management. We seek to write as much attractively priced business as is available to us and then manage our capital accordingly. We generally seek to raise capital when we forecast increased demand in the market, at times by accessing capital through joint ventures or other structures, and seek to return capital to our shareholders or joint venture investors when the demand for our coverages appears to decline and when we believe a return of capital would be beneficial to our shareholders or joint venture investors. In using joint ventures, we aim to leverage our access to business and our underwriting capabilities on an efficient capital base, develop fee income, generate profit commissions, diversify our

For the year ended December 31, 2017, our Property and Casualty and Specialty segments accounted for 51.5% and 48.5%, respectively, of our gross premiums written. Operating results relating to our segments are included in “Part II, Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

The following table shows gross premiums written allocated between our segments:

The following table shows gross premiums written in our Property segment allocated by class of business:

We write casualty and specialty reinsurance and insurance covering primarily targeted classes of business where we believe we have a sound basis for underwriting and pricing the risk we assume. Principally all of the business is reinsurance, however our book of insurance business has been increasing in recent periods, and may continue to do so. The following table shows gross premiums written in our Casualty and Specialty segment allocated by class of business:

Our Other category primarily includes the results of: (1) our share of strategic investments in certain markets we believe offer attractive risk-adjusted returns or where we believe our investment adds value, and where, rather than assuming exclusive management responsibilities ourselves, we partner with other market participants; (2) our investment unit which manages and invests the funds generated by our consolidated operations; (3) corporate expenses, certain expenses related to the acquisition of Platinum, capital servicing costs and noncontrolling interests; and (4) the remnants of our former Bermuda-based insurance operations.

Our exposures are generally diversified across geographic zones, but are also a function of market conditions and opportunities. Our largest exposure has historically been to the U.S. and Caribbean market, which represented 56.4% of our gross premiums written for the year ended December 31, 2017. A significant amount of our U.S. and Caribbean premium provides coverage against windstorms (mainly U.S. Atlantic hurricanes), earthquakes and other natural and man-made catastrophes.

The following table sets forth the amounts and percentages of our gross premiums written allocated to the territory of coverage exposure:

DaVinci was established in 2001 and principally writes property catastrophe reinsurance and certain low frequency, high severity specialty reinsurance lines of business on a global basis. In general, we seek to construct for DaVinci a portfolio with risk characteristics similar to those of Renaissance Reinsurance’s property catastrophe reinsurance portfolio, and from time to time, certain lines of specialty reinsurance written by Renaissance Reinsurance such as terrorism and workers’ compensation. In accordance with DaVinci’s underwriting guidelines, it can only participate in business also underwritten by Renaissance Reinsurance. We maintain majority voting control of DaVinci’s holding company, DaVinciRe, and accordingly, consolidate the results of DaVinciRe into our consolidated results of operations and financial position. The underwriting results of DaVinciRe are principally included in our Property segment. We seek to manage DaVinci’s capital efficiently over time in light of the market opportunities and needs we perceive and believe we are able to serve. Our noncontrolling economic ownership in DaVinciRe was 22.1% at December 31, 2017 (2016 - 24.0%).

Medici is an exempted fund, incorporated under the laws of Bermuda. Medici’s objective is to invest substantially all of its assets in various insurance-based investment instruments that have returns primarily correlated to property catastrophe risk. Third-party investors subscribe for the majority of the participating, non-voting common shares of Medici. We maintain majority voting control of Medici’s parent, RenaissanceRe Fund Holdings Ltd. (“Fund Holdings”), therefore the results of Medici and Fund Holdings are consolidated in our financial statements. Our economic ownership in Medici was 26.8% at December 31, 2017 (2016 - 36.5%).

Effective November 13, 2014, we incorporated Upsilon Fund, an exempted Bermuda limited segregated accounts company. Upsilon Fund was formed to provide a fund structure through which third party investors can invest in property reinsurance risk managed by us. As a segregated accounts company, Upsilon Fund is permitted to establish segregated accounts to invest in and hold identified pools of assets and liabilities. Each pool of assets and liabilities in each segregated account is ring-fenced from any claims from the creditors of Upsilon Fund’s general account and from the creditors of other segregated accounts within Upsilon Fund. Third party investors purchase redeemable, non-voting preference shares linked to specific segregated accounts of Upsilon Fund and own 100% of these shares. Upsilon Fund is managed by RenaissanceRe Fund Management Ltd. in return for a management fee and performance based incentive fee. We have not provided any financial or other support to Upsilon Fund that we were not contractually required to provide. Currently, Upsilon Fund is invested in Upsilon RFO and Medici.

Effective November 7, 2016, Fibonacci Re, a Bermuda-domiciled SPI, was formed to provide collateralized capacity to Renaissance Reinsurance and its affiliates. Fibonacci Re raised capital from third party investors and us via a private placement of participating notes that are listed on the Bermuda Stock Exchange. This arrangement enables Renaissance Reinsurance to support its clients with additional property catastrophe reinsurance capacity and we believe it provides attractive risk-adjusted returns to our capital partners. We concluded that Fibonacci Re meets the definition of a VIE as it does not have sufficient equity capital to finance its activities. Therefore, we evaluated our relationship with Fibonacci Re and concluded we are not the primary beneficiary of Fibonacci Re as we do not have power over the activities that most significantly impact the economic performance of Fibonacci. As a result, we do not consolidate the financial position and results of operations of Fibonacci. Other than our investment in the participating notes of Fibonacci Re, we have not provided financial or other support to Fibonacci Re that we were not contractually required to provide.

Reserve Risk. Reserve risk is a subcomponent of assumed risk. We define reserve risk as the risks related to our reserve for net claims and claim expenses, including the amount, both absolute and relative, of our outstanding reserve for net claims and claim expenses, and the impact of economic, social, legal and regulatory matters. Our reserve for net claims and claim expenses is subject to significant uncertainty and has the potential to develop adversely in future periods. While reserve risk may increase in both absolute terms and relative to its overall consideration in our ERM framework, we employ robust resources, procedures and technology to identify, understand, quantify and manage this risk. Our reserving methodologies and sensitivities for each respective line of business described in “Part II. Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations, Summary of Critical Accounting Estimates, Claims and Claim Expense Reserves.”

Controls and Compliance Committee.  We believe that a key component of our current operational risk management platform is our Controls and Compliance Committee. The Controls and Compliance Committee is comprised of our Chief Financial Officer, Group General Counsel and Chief Compliance

Ongoing Development and Enhancement.  We seek to reflect and categorize risks we monitor in part through quantitative risk distributions, even where we believe that such quantitative analysis is not as robust or well developed as our tools and models for measuring and evaluating other risks, such as catastrophe and market risks. We also seek to improve the methods by which we measure risks and believe effective risk management is a continual process that requires ongoing improvement and development. We seek from time to time to identify effective new practices or additional developments both from within our industry and from other sectors. We believe that our ongoing efforts to embed ERM throughout our organization help us produce and maintain a competitive advantage and achieve our corporate goals.

We believe the most significant accounting judgment made by management is our estimate of claims and claim expense reserves. Claims and claim expense reserves represent estimates, including actuarial and statistical projections at a given point in time, of the ultimate settlement and administration costs for unpaid claims and claim expenses arising from the insurance and reinsurance contracts we sell. We establish our claims and claim expense reserves by taking claims reported to us by insureds and ceding companies, but which have not yet been paid (“case reserves”), adding estimates for the anticipated cost of claims incurred but not yet reported to us, or incurred but not enough reported to us (collectively referred to as “IBNR”) and, if deemed necessary, adding costs for additional case reserves which represent our estimates for claims related to specific contracts previously reported to us which we believe may not be adequately estimated by the client as of that date, or adequately covered in the application of IBNR.

Our reserving techniques, assumptions and processes differ among our Property and Casualty and Specialty segments. Refer to “Note 8. Reserve for Claims and Claim Expenses in our Notes to the Consolidated Financial Statements” for more information on the risks we insure and reinsure, the reserving techniques, assumptions and processes we follow to estimate our claims and claim expense reserves, prior year development of the reserve for claims and claim expenses, analysis of our incurred and paid claims development and claims duration information for each of our Property and Casualty and Specialty

For additional information regarding our investment portfolio, refer to “Part II, Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations, Liquidity and Capital Resources, Investments” and “Note 5. Investments in our Notes to the Consolidated Financial Statements”.

Our portfolio of business continues to be characterized by relatively large transactions with ceding companies with whom we do business, although no current relationship exceeds 10% of our gross premiums written. Accordingly, our gross premiums written are subject to significant fluctuations depending on our success in maintaining or expanding our relationships with these customers. We believe that our willingness and ability to design customized programs and to provide bespoke risk management products has helped us to develop long-term relationships with brokers and customers.

Our brokers assess client needs and also perform data collection, contract preparation and other administrative tasks, enabling us to market our products cost effectively by maintaining a smaller staff. In recent years, our distribution has become increasingly reliant on a small and relatively decreasing number of broker relationships reflecting consolidation in the broker sector. We expect this concentration to continue and perhaps increase. In 2017, three brokerage firms accounted for 76.4% of our gross premiums written.

The following table shows the number of brokers for which we issued authorization for coverage on programs, the number of program submissions received and the number and percent of authorizations issued, allocated between our Property and Casualty and Specialty segments:

At February 2, 2018, we employed 384 people worldwide (February 17, 2017 - 376, February 18, 2016 - 376). None of our employees are subject to collective bargaining agreements and we are not aware of any current efforts to implement such agreements at any of our subsidiaries.

General Purpose Financial Statements. All Class 3A, Class 3B and Class 4 insurers must prepare financial statements in respect of their insurance business in accordance with GAAP, IFRS or other acceptable accounting standards, which are published on the BMA website.

Statutory Financial Statements. Each Class 3A, Class 3B and Class 4 general business insurer is required to submit annual statutory financial statements as part of its statutory financial return no later than four months after the insurer’s financial year end (unless specifically extended). The GAAP or IFRS financial

Capital and Solvency Return. Class 3A, 3B and 4 insurers are also required to file a capital and solvency return in respect of their general business, which includes, among other items, the EBS, a schedule of governance and risk management, a catastrophe risk return, a schedule of loss triangles or reconciliation of net loss reserves, a schedule of eligible capital and the Enhanced Capital Requirement (“ECR”) as calculated by the Bermuda Solvency and Capital Requirement (“BSCR”) model. The consolidated information within the statutory financial statements form the starting basis for the preparation of the EBS. The EBS is, in turn, used as the basis to calculate the insurer’s ECR.

Financial Condition Report. Class 3A, 3B and 4 insurers and insurance groups are required to prepare and publish a financial condition report (“FCR”), which was introduced to the regulatory regime in 2016 as part of the measures undertaken to achieve Solvency II equivalence. The FCR provides, among other things, details of measures governing the business operations, corporate governance framework and solvency and financial performance of the insurer/insurance group.

Minimum Solvency Margin. A general business insurer’s statutory assets must exceed its statutory liabilities by an amount, equal to or greater than the prescribed minimum solvency margin (“Minimum Solvency Margin”), which varies with the category of its registration. The Minimum Solvency Margin that must be maintained by a Class 4 insurer is the greater of (i) $100.0 million, (ii) 50% of net premiums written (with a credit for reinsurance ceded not exceeding 25% of gross premiums), (iii) 15% of net aggregate loss and loss expense provisions and other insurance reserves, or (iv) 25% of the ECR, which is established by reference to the BSCR model. The Minimum Solvency Margin for a Class 3A or Class 3B insurer is the greater of (i) $1.0 million, (ii) 20% of the first $6.0 million of net premiums written; if in excess of $6.0 million, the figure is $1.2 million plus 15% of net premiums written in excess of $6.0 million, (iii) 15% of net aggregate loss and loss expense provisions and other insurance reserves, or (iv) 25% of the insurer’s ECR.

Enhanced Capital Requirement. Each Class 3A, Class 3B and Class 4 insurer is required to maintain its capital at a level at least equal to its ECR which is established by reference to either the BSCR or an approved internal capital model. In either case, the ECR shall at all times equal or exceed the respective Class 3A, Class 3B and Class 4 insurer’s Minimum Solvency Margin and may be adjusted in circumstances where the BMA concludes that the insurer’s risk profile deviates significantly from the assumptions underlying its ECR or the insurer’s assessment of its risk management policies and practices used to calculate the ECR applicable to it. While not specifically referred to in the Insurance Act, the BMA has also established a target capital level (“TCL”) for each Class 3A, Class 3B and Class 4 insurer equal to 120% of the respective ECR. While a Class 3A, Class 3B and Class 4 insurer is not currently required to maintain its statutory capital and surplus at this level, the TCL serves as an early warning tool for the BMA and failure to maintain statutory capital at least equal to the TCL will likely result in increased BMA regulatory oversight.

Minimum Liquidity Ratio. An insurer engaged in general business is required to maintain the value of its relevant assets at not less than 75% of the amount of its relevant liabilities (“Minimum Liquidity Ratio”).

Eligible Capital. To enable the BMA to better assess the quality of an insurer’s capital resources, Class 3A, Class 3B and Class 4 insurers must maintain available capital in accordance with a “three tiered capital regime”. All capital instruments are classified as either basic or ancillary capital, which in turn are classified into one of three tiers (Tier 1, Tier 2 and Tier 3) based on their "loss absorbency" characteristics (the "Tiered Capital Requirements"). Eligibility limits are then applied to each tier in determining the amounts eligible to cover regulatory capital requirement levels. The highest capital is classified as Tier 1 capital and lesser quality capital is classified as either Tier 2 capital or Tier 3 capital. Under this regime, not more than certain specified percentages of Tier 1, Tier 2 and Tier 3 capital may be used to satisfy the Class 3A, 3B and 4 insurers' Minimum Solvency Margin and ECR requirements.

Restrictions on Dividends, Distributions and Reductions of Capital. Class 3A, Class 3B and Class 4 insurers are prohibited from declaring or paying any dividends if in breach of the required Minimum Solvency Margin or Minimum Liquidity Ratio (the “Relevant Margins”) or if the declaration or payment of such dividend would cause the insurer to fail to meet the Relevant Margins. Further, Class 3A, 3B and Class 4 insurers are

Fit and Proper Controllers. The BMA maintains supervision over the controllers (as defined herein) of all Bermuda registered insurers. For so long as shares of RenaissanceRe are listed on the NYSE or another recognized stock exchange, the Insurance Act requires that the BMA be notified in writing within 45 days of any person becoming, or ceasing to be, a controller. A controller includes the managing director and chief executive of the registered insurer or its parent company; a 10%, 20%, 33% or 50% shareholder controller; and any person in accordance with whose directions or instructions the directors of the registered insurer or of its parent company are accustomed to act. In addition, all Bermuda insurers are also required to give the BMA written notice of the fact that a person has become, or ceased to be, a controller or officer of the registered insurer within 45 days of becoming aware of such fact. An officer in relation to a registered insurer includes a director, secretary, chief executive or senior executive by whatever name called.

Material Change. All registered insurers are required to give the BMA 30 days’ notice of certain matters that are likely to be of material significance to the BMA in carrying out its supervisory function under the Insurance Act. The Insurance Act prescribes which matters require advance notice.

Insurance Code of Conduct. All Bermuda insurers are required to comply with the BMA’s Insurance Code of Conduct, which establishes duties, requirements and standards to be complied with to ensure each insurer implements sound corporate governance, risk management and internal controls. Failure to comply with these requirements will be a factor taken into account by the BMA in determining whether an insurer is conducting its business in a sound and prudent manner under the Insurance Act.

Special Purpose Insurer Reporting Requirements. Unlike other (re)insurers, SPIs are fully funded to meet their (re)insurance obligations; therefore the application and supervision processes are streamlined to facilitate the transparent structure. Further, the BMA has the discretion to modify such insurer’s accounting requirements under the Insurance Act. Like other (re)insurers, the principal representative of an SPI has a duty to inform the BMA in relation to solvency matters, where applicable. During 2016, new legislative requirements were introduced requiring SPIs to file annual statutory or modified financial returns via an electronic filing system. Under these requirements, SPIs are required to map GAAP financial statements to the electronic statutory forms and are required to provide information around ownership structure, assessment of risks, analyses of premium and details of segregated cells.

Insurance Manager Reporting Requirements. During 2016, the BMA undertook to enhance its oversight of insurance managers as part of the development of Bermuda’s insurance regulatory framework. As part of this, the BMA introduced the Insurance Manager Code of Conduct and required insurance managers to file specific details via an Insurance Manager’s Return. The Insurance Manager’s Return requires, among other things, details around directors and officers of the insurance manager, the services provided by the entity, and details of the insurers managed by the insurance manager.

Group Supervision. Pursuant to the Insurance Act, the BMA acts as the group supervisor of the RenaissanceRe group of companies (the “RenaissanceRe Group”) and it has designated Renaissance Reinsurance to be the “designated insurer” in respect of the RenaissanceRe Group. The designated insurer is required to ensure that the RenaissanceRe Group complies with the provisions of the Insurance Act pertaining to groups and all related group solvency and group supervision rules (together, the “Group Rules”). Under the Group Rules, the RenaissanceRe Group is required to annually prepare and submit to the BMA group GAAP financial statements, group statutory financial statements, a group capital and solvency return (including an EBS) and an FCR. An insurance group must ensure that the value of the insurance group's assets exceeds the amount of the insurance group's liabilities by the aggregate of: (i) the individual Minimum Solvency Margin of each qualifying member of the group controlled by the parent company; and (ii) the parent company’s percentage shareholding in the member multiplied by the member’s Minimum Solvency Margin, where the parent company exercises significant influence over a member of the group but does not control the member (the "Group Minimum Solvency Margin"). A member is a qualified member of the insurance group if it is subject to solvency requirements in the jurisdiction in which it is

Income Taxes. Currently, neither we nor our shareholders are required to pay Bermuda income or profits tax, withholding tax, capital gains tax, capital transfer tax, estate duty or inheritance tax in respect of our shares.  We have obtained an assurance from the Minister of Finance of Bermuda under the Exempted Undertakings Tax Protection Act 1966 that, if Bermuda enacts legislation imposing any tax on profits, income, capital asset, gain or appreciation or any tax in the nature of estate duty or inheritance tax, such tax shall not be applicable to us, our operations or our shares, debentures or other obligations until March 31, 2035, except insofar as such tax applies to persons ordinarily resident in Bermuda or is payable by us in respect of real property owned or leased by us in Bermuda.

Admitted Company Regulation. Renaissance Reinsurance U.S. is a Maryland-domiciled insurer licensed in 26 states and the District of Columbia and qualified or certified as a reinsurer in an additional 24 states. As a U.S. licensed and authorized insurer, Renaissance Reinsurance U.S. is subject to considerable regulation and supervision by state insurance regulators. The extent of regulation varies but generally has its source in statutes that delegate regulatory, supervisory and administrative authority to a department of insurance in each state. Among other things, state insurance departments regulate insurer solvency, authorized investments, loss and loss adjustment expense and unearned premium reserves, and deposits of securities for the benefit of policyholders. State insurance departments also conduct periodic examinations of the affairs of authorized insurance companies and require the filing of annual and other reports relating to the financial condition of companies and other matters. The Maryland Insurance Administration, as Renaissance Reinsurance U.S.’s domestic regulator, is the primary financial regulator of Renaissance Reinsurance U.S. We are pursuing growth in many of lines of business written by Renaissance Reinsurance U.S., which may increase the impact of U.S. regulation on our business as a whole.

Holding Company Regulation. We are subject to the insurance holding company laws of Maryland, the domestic state of Renaissance Reinsurance U.S. These laws generally require Renaissance Reinsurance U.S. to file certain reports concerning its capital structure, ownership, financial condition and general

Effective for 2014, Maryland adopted enterprise risk management and reporting obligations applicable to insurance holding company systems that are meant to protect the licensed companies from enterprise risk. These obligations include requiring an annual enterprise risk report by the ultimate controlling person identifying the material risks within the insurance holding company system that could pose enterprise risk to the U.S. licensed companies. We timely filed our enterprise risk reports with the Maryland Insurance Administration for 2016 and 2017.

Reinsurance Regulation. The insurance laws of each U.S. state regulate the sale of reinsurance to licensed ceding insurers by non-admitted alien reinsurers acting from locations outside the state. With some exceptions, the sale of insurance within a jurisdiction where the insurer is not admitted to do business is prohibited. Our Bermuda-domiciled insurance operations and joint ventures (principally Renaissance Reinsurance, DaVinci, Top Layer Re, RenaissanceRe Specialty U.S. and Upsilon RFO) are all admitted to transact insurance business in Bermuda and do not maintain an office or solicit, advertise, settle claims or conduct other insurance activities in any other jurisdiction where the conduct of such activities would require that any company be so admitted.

NAIC Ratios. The NAIC has established 13 financial ratios to assist state insurance departments in their oversight of the financial condition of licensed property and casualty insurance companies operating in their respective states. The NAIC’s Insurance Regulatory Information System (“IRIS”) calculates these ratios based on information submitted by insurers on an annual basis and shares the information with the applicable state insurance departments. Each ratio has an established “usual range” of results and assists state insurance departments in executing their statutory mandate to oversee the financial condition of insurance companies. A ratio result falling outside the usual range of IRIS ratios is not considered a failing result; rather unusual values are viewed as part of the regulatory early monitoring system. Furthermore, in some years, it may not be unusual for financially sound companies to have several ratios with results outside the usual ranges. An insurance company may fall outside of the usual range for one or more ratios because of specific transactions that are themselves immaterial.

Federal Oversight and Other Government Intervention. Government intervention in the insurance and reinsurance markets in the U.S. continues to evolve. Although U.S. state regulation is currently the primary form of regulation of insurance and reinsurance, Congress has considered proposals in several areas that may impact the industry, including the creation of an optional federal charter, repeal of the insurance company antitrust exemption from the McCarran Ferguson Act, and tax law changes, including changes to increase the taxation of reinsurance premiums paid to off-shore affiliates with respect to U.S. risks and comprehensive business tax reform legislation including border adjustments. We are unable to predict what other proposals will be made or adopted or the effect, if any, that such proposals would have on our operations and financial condition.

recommending certain changes to the FSOC’s process for designating nonbank financial companies as systemically significant in order to make the designation process more rigorous, clear, and transparent. Any suggested changes ultimately adopted by the FSOC would be implemented by FSOC directly, rather than through legislation.

The Dodd-Frank Act authorizes Treasury and the Office of the U.S. Trade Representative (“USTR”) to enter into international agreements of mutual recognition regarding the prudential regulation of insurance or reinsurance (“covered agreements”). In January 2017, Treasury and the USTR negotiated a covered agreement with the EU regarding the prudential regulation of insurance and reinsurance (the “US-EU Covered Agreement”), which was signed in September 2017. Each party has begun the process of completing its internal requirements and procedures (such as amending or promulgating appropriate statutes and regulations) in order for the US-EU Covered Agreement to enter into force.

General.  The operations of RSML are subject to oversight by Lloyd’s, substantially effected through the Lloyd’s Franchise Board. RSML’s business plan for Syndicate 1458, including maximum underwriting capacity, requires annual approval by the Lloyd’s Franchise Board. The Lloyd’s Franchise Board may require changes to any business plan presented to it or additional capital to be provided to support the underwriting plan. Lloyd’s also imposes various charges and assessments on its members. If material changes in the business plan for Syndicate 1458 were required by the Lloyd’s Franchise Board, or if charges and assessments payable to Lloyd’s by RenaissanceRe CCL were to increase significantly, these events could have an adverse effect on the operations and financial results of RSML. We have deposited

Capital Requirements.  The underwriting capacity of a member of Lloyd’s must be supported by providing a deposit (referred to as “Funds at Lloyd’s”) in the form of cash, securities or letters of credit in an amount determined under the capital adequacy regime of the U.K.’s Prudential Regulation Authority (the “PRA”). The amount of such deposit is calculated for each member through the completion of an annual capital adequacy exercise. Under these requirements, Lloyd’s must demonstrate that each member has sufficient assets to meet its underwriting liabilities plus a required solvency margin.

Restrictions.  A Reinsurance to Close (“RITC”) generally is put in place after the third year of operations of a syndicate year of account. On successful conclusion of a RITC, any profit from the syndicate’s operations for that year of account can be remitted by the managing agent to the syndicate’s members. If the syndicate’s managing agency concludes that an appropriate RITC cannot be determined or negotiated on commercially acceptable terms in respect of a particular underwriting year, it must determine that the underwriting year remain open and be placed into run-off. During this period, there cannot be a release of the Funds at Lloyd’s of a member of that syndicate without the consent of Lloyd’s.

Intervention Powers.  The Council of Lloyd’s has wide discretionary powers to regulate members’ underwriting at Lloyd’s. It may, for instance, change the basis on which syndicate expenses are allocated or vary the Funds at Lloyd’s requirements or the investment criteria applicable to the provision of Funds at Lloyd’s. Exercising any of these powers might affect the return on the corporate member’s participation in a given underwriting year. If a member of Lloyd’s is unable to pay its debts to policyholders, the member may obtain financial assistance from the Lloyd’s Central Fund, which in many respects acts as an equivalent to a state guaranty fund in the U.S. If Lloyd’s determines that the Central Fund needs to be increased, it has the power to assess premium levies on current Lloyd’s members. The Council of Lloyd’s has discretion to call or assess up to 3% of a member’s underwriting capacity in any one year as a Central Fund contribution.

Change of Control.  The PRA and the FCA currently regulate the acquisition of control of any Lloyd’s managing agent which is authorized under the FSMA. Any company or individual that, together with its or his associates, directly or indirectly acquires 10% or more of the shares in a Lloyd’s managing agent or its parent company, or is entitled to exercise or control the exercise of 10% or more of the voting power in such Lloyd’s managing agent or its parent company, would be considered to have acquired control for the purposes of the relevant legislation, as would a person who had significant influence over the management of such Lloyd’s managing agent or its parent company by virtue of their shareholding or voting power in either. A purchaser of 10% or more of RenaissanceRe’s common shares or voting power would therefore be considered to have acquired control of RSML. Under the FSMA, any person or entity proposing to acquire control over a Lloyd’s managing agent must give prior notification to the PRA and the FCA of their or the entity’s intention to do so. The PRA and FCA would then have 60 working days to consider the application to acquire control. Failure to make the relevant prior application could result in action being taken against RSML by the PRA or the FCA or both of them. Lloyd’s approval is also required before any person can acquire control (using the same definition as for the PRA and FCA) of a Lloyd’s managing agent or Lloyd’s corporate member.

Other Applicable Laws.  Lloyd’s worldwide insurance and reinsurance business is subject to various regulations, laws, treaties and other applicable policies of the EU, as well as of each nation, state and locality in which it operates. Material changes in governmental requirements and laws could have an adverse effect on Lloyd’s and market participants, including RSML and RenaissanceRe CCL.

GLOSSARY OF SELECTED INSURANCE AND REINSURANCE TERMS

We maintain a website at www.renre.com. The information on our website is not incorporated by reference in this Form 10-K. We make available, free of charge through our website, our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish such material to, the U.S. Securities and Exchange Commission (the “SEC”). We also make available, free of charge from our website, our Audit Committee Charter, Compensation and Corporate Governance Committee Charter, Corporate Governance Guidelines, and Code of Ethics. Such information is also available in print for any shareholder who sends a request to RenaissanceRe Holdings Ltd., Attn: Office of the Corporate Secretary, P.O. Box HM 2527, Hamilton, HMGX, Bermuda. Reports filed with the SEC may also be viewed or obtained at the SEC Public Reference Room at 100 F Street, N.E., Washington, DC 20549. Information on the operation of the SEC Public Reference Room may be obtained by calling the SEC at 1-800-SEC-0330. The SEC maintains an internet site that contains reports, proxy and information statements, and other information regarding issuers, including the Company, that file electronically with the SEC. The address of the SEC’s website is www.sec.gov.

The following table sets forth, for the periods indicated, the high and low prices per share of our common shares as reported in composite NYSE trading: