How do I analyze merger arbitrage spreads and size positions?

Question

AcadiFi · Accepted Answer

Merger arbitrage spread analysis blends probability-weighted return, break risk, and portfolio construction. For a deal with target price $85, current $81.50, announced deal price $85, spread = 4.2%. Compute annualized return: 4.2% × (365/60) = 25.6% annualized if the deal closes on time. Risk assessment. First, estimate P(close). Cash deals with clear regulatory path typically close 90-95%. Stock deals with financing contingencies 75-85%. Cross-border deals with CFIUS review 70-85%. Consider Brightfall Corp acquiring Kestrel Analytics. Horizontal combination, FTC Second Request expected. P(close) estimated at 88%. Second, estimate downside if break: unaffected price before announcement was $62, so downside = ($62 - $81.50) / $81.50 = -24%. Expected return = 0.88 × 4.2% + 0.12 × (-24%) = 3.7% - 2.9% = 0.8%. Annualized = 4.9%. That's a thin margin; likely pass unless spread widens. Third, calendar risk: regulatory review can extend closing by 30-90 days; each month delay reduces annualized IRR. Fourth, competing bid probability: if strategic rivals exist, upside option value adds 0.5-2% to expected return. Position sizing. Apply Kelly or half-Kelly: fraction = (edge) / (variance). For a 0.8% edge with 15% position volatility, Kelly fraction is roughly 3.5%. Never exceed 5% in any single deal. Across a 30-50 deal portfolio, total gross exposure 120-180%, diversified across sectors and deal types. Monitor antitrust filings, proxy votes, SEC approvals daily. Hedge currency on cross-border deals. Average merger arb returns 5-7% net with vol 4-6%.

How do I analyze merger arbitrage spreads and size positions?

Master Level III with our CFA Course

Related Questions

Practice Questions