FRM Exam Part II · Hedge Fund Investment Strategies

Event-Driven Strategies: Merger Arbitrage and Distressed Debt

Updated 11 October 2026 · Fact-checked

Event-driven strategies profit from corporate events such as mergers, bankruptcies and activism. Merger arbitrage buys the target and earns the spread between the deal price and the market price, a payoff like selling a put option. Distressed investing buys troubled debt below expected recovery value. Solve questions by naming the event, payoff and risk.

Understand Event-Driven Strategies: Merger Arbitrage and Distressed Debt

Event-driven hedge funds do not bet on the market direction. They bet that a specific corporate event will happen, and they earn a return for bearing the risk that it fails or drags on. The main types are merger arbitrage (also called risk arbitrage), distressed securities and activism.

In merger arbitrage, a bidder offers to buy a target. The target's share price trades below the offer price. The gap is the deal spread. The fund buys the target. In a stock deal it also shorts the acquirer in the exchange ratio to hedge market and acquirer price moves. If the deal closes, the fund earns the spread. If the deal breaks, the target price usually falls sharply back toward its undisturbed price.

This gives a payoff with a small, frequent gain and a rare, large loss. It looks like selling an out-of-the-money put option on the target (or on the deal). The spread is the premium collected. The deal-break loss is the put payout. Returns are therefore negatively skewed and show tail risk, and they correlate with equity markets in sharp sell-offs, because deals break and spreads widen when markets fall. Merger arbitrage is a low-beta in normal times, rising beta in stress strategy.

In distressed investing, the fund buys bonds, loans or other claims of a company in or near default, at prices well below par. It profits if the recovery from restructuring or bankruptcy exceeds the price paid. The key skills are valuing the firm, understanding the capital structure and priority of claims, and judging legal process and timing. Risks are low recovery, long delays, illiquidity, and valuation uncertainty. Some funds take the fulcrum security, the class that will receive the reorganised equity, to gain control.

Activist funds take a stake in a listed company and push for change, such as a board seat, buyback, asset sale or strategy shift. The return comes from the price rise if management responds. Risks are concentrated positions, a long time horizon, cost of campaigns, and illiquidity if the stake is large. The three strategies differ: merger arbitrage has a defined, short-dated event and capped upside; distressed and activist strategies have uncertain outcomes and timing, with wider payoff ranges.

Key formulas to remember

Deal spread (cash deal): Spread = Offer price − Target market price; Gross profit per share if the deal closes. Express as % of market price for comparison.
Annualised spread: Annualised return ≈ (Spread ÷ Target price) × (365 ÷ days to close); Simple annualisation. Needed to compare deals with different closing dates.
Implied deal-completion probability: Market price = p × Offer price + (1 − p) × Break price, so p = (Price − Break price) ÷ (Offer − Break price); Ignores time value and dividends. Use it to read what the market believes.
Stock deal hedge: Short exchange ratio × acquirer shares per target share bought; If the target gets 0.5 acquirer shares per share, short 0.5 acquirer shares per target share held.
Payoff profile: Merger arbitrage ≈ short out-of-the-money put on the target; Gain is capped at the spread. Loss is Price − Break price if the deal fails.
Distressed return: Return = (Recovery value − Purchase price) ÷ Purchase price; Recovery is measured in present value terms, after costs and delay.

How to solve Event-Driven Strategies: Merger Arbitrage and Distressed Debt questions

Use this method for any question on event-driven strategies. Most questions ask you to identify the strategy, the payoff or the main risk.

1Name the event: announced deal, default or restructuring, or activist campaign.
2Identify the position: long target (and short acquirer if a stock deal), long distressed claim, or long stake with engagement.
3Write the payoff: capped gain if the event happens, larger loss if it fails (merger arbitrage); recovery minus price (distressed).
4Calculate the spread, implied probability or recovery return if numbers are given. Check units and time.
5Name the key risk: deal break, timing delay, regulatory block, financing failure, low recovery, illiquidity, legal outcome.
6Link to portfolio behaviour: negative skew, put-like payoff, and correlation with equities in stress.
7Pick the option that matches the strategy's exact mechanics and rejects directional or market-wide claims.

Quickest way: Spread, probability, put analogy

When to use it: Use for numeric merger arbitrage questions or when a question asks about payoff shape.

Spread = offer − price. Gain if the deal closes.
Downside = price − break price. Loss if it fails.
Compare: a small gain against a large loss means a short-put shape.
Implied probability p = spread-adjusted: (price − break) ÷ (offer − break).
For distressed, compare expected recovery with price. Check priority of the claim.

Common mistakes in Event-Driven Strategies: Merger Arbitrage and Distressed Debt

Saying merger arbitrage is a bet on the market direction.
Students link all equity long positions to beta.
Fix: It is a bet on deal completion. Beta is low in normal times, but losses cluster in market stress.
Describing the payoff as a long put or a long call.
The put analogy is remembered but not its direction.
Fix: The fund collects a small premium (spread) and bears the large loss: it is short a put.
Shorting the target in a stock deal.
Confusion about which leg is the hedge.
Fix: Buy the target and short the acquirer. The short hedges the acquirer price risk in the exchange ratio.
Quoting the raw spread as the return without time.
A 3% spread looks the same whether it closes in one month or twelve.
Fix: Annualise using days to close, and note that delay reduces return.
Treating distressed debt as simply high-yield investing.
Both buy low-rated bonds.
Fix: Distressed investing depends on recovery, priority of claims and legal process, not on coupon income.
Calling activism a market-neutral arbitrage.
All three are grouped as event-driven.
Fix: Activists hold concentrated, long-biased, illiquid positions and rely on management response.

Worked examples

Example 1

A bidder offers ₹... Use USD: A bidder offers USD 50 per share in cash for a target. The target trades at USD 48. If the deal fails, the price is expected to fall to USD 36. The deal is expected to close in 90 days. Find the implied probability of completion and the simple annualised return if the deal closes.

Show the solution

Spread = 50 − 48 = USD 2.
Return if closed = 2 ÷ 48 = 4.167%.
Annualised ≈ 4.167% × (365 ÷ 90) = 4.167% × 4.0556 = 16.90%.
Implied probability p = (48 − 36) ÷ (50 − 36) = 12 ÷ 14 = 0.857.

Answer: Implied completion probability is about 85.7% and the simple annualised return if the deal closes is about 16.9%.

Example 2

A fund buys a target in a stock-for-stock deal. Each target share receives 0.8 acquirer shares. The fund buys 10,000 target shares. How should it hedge, and which risk remains?

Show the solution

The target is valued by reference to the acquirer: each target share is worth 0.8 acquirer shares.
Hedge by shorting 0.8 × 10,000 = 8,000 acquirer shares.
This removes most of the exposure to the acquirer's share price move.
The remaining risk is deal break: the target falls back and the short acquirer position no longer offsets the loss. Timing and regulatory risk also remain.

Answer: Short 8,000 acquirer shares. The remaining main risk is that the deal fails, giving a large loss similar to a short put payout.

Exam tips

If an option asks for the payoff shape of merger arbitrage, choose the short put or negative skew answer.
Check which leg is long and which is short in a stock deal: long target, short acquirer.
For distressed questions, look for words like recovery, priority and fulcrum security.
Expect scenario questions where a market sell-off widens spreads. The answer is that merger arbitrage correlation to equities rises in stress.
Read carefully if the question asks for annualised or simple return.

Practice questions from Hedge Fund Investment Strategies

Event-Driven Strategies: Merger Arbitrage and Distressed Debt in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Event-Driven Strategies: Merger Arbitrage and Distressed Debt: frequently asked questions

How does merger arbitrage make money?

The fund buys the target at a discount to the offer price and holds until the deal closes. The profit is the deal spread. It is paid for taking the risk that the deal fails.

Why is merger arbitrage compared to selling a put option?

Both give a small, frequent gain and a rare, large loss. The spread is like the option premium and the deal-break price fall is like the put payout.

What is the difference between risk arbitrage and distressed investing?

Risk arbitrage bets on a defined event, a merger closing, with capped upside. Distressed investing buys troubled claims and relies on recovery value, legal process and timing, with a wider range of outcomes.

What is a fulcrum security?

It is the class of claim in a restructuring that is expected to receive the new equity of the reorganised firm. Holding it can give the investor influence over the outcome.