The Purpose of Reinsurance

Reinsurance is insurance for insurance companies. Primary insurers purchase reinsurance to reduce their exposure to large losses, stabilize financial results, increase their capacity to write new business, and manage their capital more efficiently. Without reinsurance, a single catastrophic event could threaten the solvency of an insurer. The global reinsurance market facilitates the distribution of risk across entities worldwide, ensuring that no single company bears more exposure than it can safely absorb.

The value of reinsurance extends beyond pure risk transfer. By ceding a portion of their risk, primary insurers free up capital that can be deployed to write additional business. Reinsurers also provide technical expertise, market intelligence, and access to global data that can help primary insurers improve their underwriting and pricing. For smaller or newer insurers, a reinsurance relationship with a well-rated reinsurer enhances credibility and financial strength in the eyes of regulators and policyholders.

Treaty vs. Facultative Reinsurance

The reinsurance market operates through two primary mechanisms. Treaty reinsurance covers an entire portfolio or defined class of business automatically. Once a treaty is in place, all policies meeting the treaty's terms are ceded without individual negotiation. This is the more common form and accounts for the majority of reinsurance premiums. Treaty reinsurance is negotiated annually, typically during major renewal seasons in January (the largest), April, June, and July.

Facultative reinsurance covers individual risks on a case-by-case basis. The primary insurer submits a specific risk to the reinsurance market, and reinsurers decide whether to participate and at what price. Facultative placements are common for large or unusual risks that fall outside the scope of existing treaties, such as a major commercial property account or a unique liability exposure. The facultative process is more labor-intensive than treaty placement but provides flexibility for risks that do not fit standard treaty terms.

Proportional and Non-Proportional Structures

Within both treaty and facultative reinsurance, there are proportional and non-proportional structures. Proportional reinsurance (also called pro rata) shares premiums and losses between the cedant and reinsurer in agreed proportions. Quota share treaties cede a fixed percentage of every policy (for example, 25% of all premiums and losses). Surplus share treaties cede amounts above the cedant's retention on a risk-by-risk basis.

Non-proportional reinsurance (also called excess of loss) pays only when losses exceed a specified attachment point. Per-occurrence excess of loss covers individual events, while aggregate excess of loss covers cumulative losses over a period. Catastrophe excess of loss specifically covers losses from catastrophic events. Non-proportional reinsurance is priced based on the probability and expected severity of losses penetrating the layer, using techniques like burning cost analysis and exposure rating discussed in other articles in this series.

Major Market Participants

The traditional reinsurance market is dominated by a relatively small number of large global reinsurers. Munich Re (based in Germany) and Swiss Re (based in Switzerland) are the two largest, each writing tens of billions of dollars in annual premium. Hannover Re, SCOR, Berkshire Hathaway, and Lloyd's syndicates are also major players. These companies have the capital base, diversification, and technical expertise to absorb large concentrations of risk from primary insurers worldwide. Major reinsurance hubs include Munich, Zurich, London, Bermuda, and Singapore.

Reinsurance brokers serve as intermediaries between primary insurers (cedants) and reinsurers. The three largest brokers (Aon, Guy Carpenter, and Gallagher Re) handle the majority of treaty placements globally. Brokers provide market access, negotiation expertise, analytical support, and placement services. They help cedants structure their reinsurance programs, solicit competitive quotes from multiple reinsurers, and negotiate terms on behalf of their clients.

Alternative Capital and Convergence

Over the past two decades, alternative capital from pension funds, hedge funds, sovereign wealth funds, and other institutional investors has become an increasingly important source of reinsurance capacity. These investors access reinsurance risk through insurance-linked securities (ILS), catastrophe bonds, industry loss warranties, and collateralized reinsurance vehicles. Alternative capital now represents roughly 15% to 20% of global reinsurance capacity, concentrated primarily in property catastrophe risk where the exposure is well-modeled and time-limited.

The attraction for institutional investors is that catastrophe risk has low correlation with financial market risk, providing diversification benefits for their broader portfolios. The attraction for cedants is additional capacity and potentially lower pricing when alternative capital supplements traditional reinsurer capacity. The convergence of insurance and capital markets continues to evolve, with newer structures enabling alternative capital to participate in a broader range of reinsurance risks beyond just catastrophe exposure.

Common Pitfalls

A common mistake for primary insurers is purchasing reinsurance without a clear understanding of how it fits into their overall risk management and capital strategy. Reinsurance should be structured to address specific risks and capital needs rather than purchased purely on price. Another pitfall is overreliance on a single reinsurer, which creates counterparty concentration risk. If that reinsurer experiences financial difficulty, the cedant may not recover the amounts it is owed. Diversifying reinsurance placements across multiple reinsurers and monitoring their financial strength reduces this risk.

Study Tips

For exam preparation, understand the distinction between treaty and facultative reinsurance and when each is appropriate. Be comfortable explaining proportional versus non-proportional structures and the key features of each (quota share, surplus share, per-occurrence excess, catastrophe excess, aggregate excess). Know the major participants in the global reinsurance market and the role of brokers in the placement process. Review how alternative capital participates in reinsurance markets and why institutional investors find catastrophe risk attractive. Finally, understand how reinsurance affects a primary insurer's financial statements, capital requirements, and competitive positioning.

Reinsurance Markets: How Risk Gets Spread Globally