Merger Arbitrage Spread

The difference between a target company's current stock price and the implied value of an acquisition offer.

The merger arbitrage spread represents the difference between the current market price of an acquisition target's stock and the implied value of the announced buyout offer. In a pending merger or acquisition, the target company's stock typically trades at a discount to the offer price. This discount exists because of the time value of money and, more importantly, the risk that the transaction might fail to close due to regulatory hurdles, shareholder rejection, financing issues, or material adverse changes. Arbitrageurs monitor this spread to gauge the market's collective confidence in a deal's completion. A narrow spread suggests the market believes the transaction is highly likely to close smoothly and quickly. Conversely, a wide spread indicates significant skepticism, regulatory friction, or an extended timeline to completion. If a deal collapses entirely, the target stock usually falls sharply back to its pre-announcement level, causing steep losses for arbitrageurs. To calculate the spread in a cash deal, an investor subtracts the current target stock price from the cash offer price. In a stock-for-stock deal, the investor must first calculate the implied deal value by multiplying the exchange ratio by the acquirer's current stock price, then subtract the target's current stock price. This spread is often annualized to compare the potential return against other risk-free or low-risk investment yields.

Company A announces it will acquire Company B in an all-stock transaction, offering 0.5 shares of Company A for every 1 share of Company B. If Company A currently trades at $100, the implied deal value is $50 per share (0.5 $100). If Company B's stock is currently trading in the market at $47, the merger arbitrage spread is $3.00 per share ($50.00 - $47.00), representing a gross spread of 6.38%.