Mergers and acquisitions (M&A)

M&A is the highest-margin business in investment banking by a wide margin. The fee on a $5 billion sell-side advisory mandate can run $40-80 million for the lead advisor. The cost of execution — a small team, a few months — is tiny relative to the fee. This is why every bank fights for M&A market share, and why elite boutiques have built billion-dollar businesses on advisory alone.

Sell-side vs buy-side

M&A divides into sell-side and buy-side mandates. On the sell-side, the bank represents a company that is putting itself up for sale (or a division that the parent wants to divest). The work begins with valuation, then preparation of marketing materials (a Confidential Information Memorandum, the 'CIM'), then a controlled auction process with potential buyers (typically other strategics in the industry and financial sponsors / private equity), then negotiation of price and terms, then closing. The fee is contingent on a deal closing — typically 0.5% to 1.5% of transaction value, scaled to the size of the deal.

On the buy-side, the bank represents an acquirer. The work is similar in structure but the dynamics differ: the buy-side advisor helps identify targets, run financial analysis, structure financing, and negotiate. Buy-side fees are usually smaller (often a fixed fee plus a smaller success component) because the buyer typically shops the deal across multiple potential advisors before committing.

Fairness opinions

A specific deliverable that almost always falls to the M&A bank is the fairness opinion. This is a written legal opinion, signed by the bank, that the consideration paid (or received) in a transaction is fair from a financial point of view to the relevant party. It is what the company's board uses to defend the transaction in the event of a shareholder lawsuit. Fairness opinions are produced by a separate fairness committee inside the bank that does not work on the deal day-to-day. They typically come with a substantial fee in their own right.

Deal structures and accretion / dilution

Specific transaction structures matter. A merger of equals, an asset sale, a stock-for-stock acquisition, a leveraged buyout, a tender offer, a SPAC merger, a divestiture, a spin-off — each has different tax consequences, different accounting treatment, different regulatory hurdles, and different financial implications for both sides. Senior bankers know these distinctions cold, and clients pay them in part for that knowledge.

Accretion / dilution — the formula

Accretion / dilution analysis is the standard test of any stock-funded M&A deal: does the transaction increase or decrease the buyer's earnings per share, both pro forma year one and after expected synergies? It is one of the simplest analyses in finance to execute and one of the most heavily fought-over in negotiation. The analysis is often the difference between a deal getting done and not.

Pro-forma EPS  =

      NI_A   +   NI_T   +   AT_synergies   −   AT_interest_on_new_debt
  ───────────────────────────────────────────────────────────────────────────
              Shares_A   +   New_shares_issued

Accretion / dilution  =  Pro-forma EPS   −   Standalone EPS_A

where:
  NI_A            =  acquirer's standalone net income, in currency units
                      — what the buyer would earn without the deal
  NI_T            =  target's net income (the cash flows being purchased)
                      — used as-is for a 100% acquisition; pro-rated for stakes
  AT_synergies    =  after-tax expected synergies from the combination
                      — pre-tax synergies × (1 − marginal tax rate)
                      — typically realized over 2-3 years post-close, with the
                        full run-rate hit by year 2 or 3 in a typical model
  AT_interest     =  after-tax interest expense on any new debt raised to fund
   on_new_debt      the deal — debt amount × interest rate × (1 − tax rate)
                      — zero in a pure all-stock deal
  Shares_A        =  acquirer's standalone diluted share count
  New_shares      =  shares issued in the deal as consideration to target holders
   issued           — for a stock deal: deal value / acquirer's share price
                      — zero in a pure all-cash deal
  Standalone      =  NI_A / Shares_A
   EPS_A            — the baseline EPS the buyer would have reported without
                      the deal; the bar that the pro-forma must clear to be
                      'accretive'

Worked example: Acquirer with USD 500m of net income, 100m shares (so EPS of USD 5.00, share price USD 100, P/E of 20x). Target with USD 100m of net income and EPS of USD 4.00 in 20m shares (share price USD 60, P/E of 15x). The acquirer offers USD 75 per target share, paid in stock — a total consideration of USD 1.5bn requiring 15m new acquirer shares. Run the formula:

Synergies assumed: zero in year 1 (conservative).

Numerator = 500 + 100 + 0 − 0 = USD 600m
Denominator = 100m + 15m = 115m shares
Pro-forma EPS = 600 / 115 = USD 5.22

Standalone EPS_A = 500 / 100 = USD 5.00

Accretion / dilution = $5.22 − $5.00 = $0.22
As a percentage of standalone: +4.4% — accretive in year 1.

Why: acquirer P/E (20x) is higher than target P/E (15x). The shareholders
get 'more earnings' per new share issued than they give up in dilution.
Matches the heuristic exactly.

Restructuring is M&A's distressed cousin. The bank advises companies (and sometimes their creditors) on Chapter 11 reorganisations, out-of-court restructurings, debt-for-equity swaps, and exchange offers. Houlihan Lokey, Lazard, PJT, and Evercore are the dominant names. Restructuring is counter-cyclical: when M&A volume falls in a recession, restructuring volume rises.