Event-Driven

In a cash deal, the manager buys the target after announcement at a price below the agreed consideration. The gap, the deal spread, is compensation for the risk that the transaction fails, is repriced, or takes longer than expected. The gross return is the offer price minus the purchase price, divided by the purchase price; annualising means scaling that figure by the number of days expected until closing relative to a full year, so a small spread on a deal closing in two months can imply a substantial annualised rate.

In a stock-for-stock deal, the manager buys the target and shorts the acquirer in the exchange ratio, isolating the spread and neutralising much of the market and sector exposure carried by the acquirer's shares. The short leg also captures any decline in the acquirer if the market judges the buyer to be overpaying.

Merger arbitrage, sometimes called risk arbitrage, is the most visible sleeve, but the category is broader. Distressed managers buy the debt or claims of companies in or near bankruptcy, forming a view on recovery values, priority of claims, and how a reorganisation plan allocates value across the capital structure; they may sit on creditor committees and shape the outcome. Activist funds accumulate a stake and then agitate for a sale, a spin-off, a buyback or board change, meaning they create the catalyst rather than react to it.

Special-situations mandates cover spin-offs, index changes, rights issues, recapitalisations and litigation outcomes. Capital-structure arbitrage trades relative mispricings between a single issuer's bonds, converts and equity when an event is expected to reprice them differently.

An announced deal that closes on schedule delivers a modest, largely predetermined gain, while a broken deal produces a rapid loss as the target falls back toward its unaffected price. The result is a distribution with many small positive outcomes and occasional large negative ones, similar in shape to a short put position: limited upside, fat left tail, and reported volatility that understates true risk.

Correlation behaves the same way. In calm markets, deal spreads grind in and returns look independent of the equity index. In a financing squeeze or a regulatory clampdown, deals break together, spreads widen across the book, and leverage forces deleveraging, so realised correlation with equities rises precisely when diversification was being relied upon. Antitrust review, political intervention, tax-rule changes and financing conditions are the recurring sources of that clustered risk.

Expect to classify a described mandate into the correct hedge-strategy bucket and to distinguish event-driven from relative value, macro and equity hedge approaches. You should be able to compute a deal spread and its annualised equivalent, explain how the hedge ratio in a stock deal is derived from the exchange ratio, and identify which leg carries the residual risk.

Be ready to evaluate the strategy from an allocator's perspective: leverage amplifies both spread capture and break losses; distressed positions carry poor liquidity and long, uncertain workout horizons, so lock-ups and gates are common; performance fees reward the frequent small wins while the tail loss is borne by the investor. Backward-looking volatility and correlation statistics therefore misstate the risk contribution of an event-driven allocation in a diversified portfolio.