A Material Adverse Effect (MAE) clause lets the buyer walk away, or refuse to complete, if the business suffers a serious deterioration between signing and completion. It is the buyer’s escape hatch for the gap between agreeing a deal and actually closing it.
Technically, it is a contractually defined threshold of deterioration in the target’s condition, financial or otherwise, which if triggered entitles the buyer to terminate or decline to complete. It is one of the most heavily negotiated definitions in the agreement, because the words used decide how easily the buyer can walk.
The buyer wants a broad definition that captures almost any negative development, giving them maximum room to reconsider if the business softens before completion. The seller wants a narrow definition limited to genuinely severe, business-specific deterioration, so ordinary trading volatility cannot be used as a pretext to renegotiate or exit.
The carve-outs do most of the real work. A well-drafted MAE clause excludes general economic and market conditions, industry-wide events, and any effect flowing from the deal itself becoming known, such as customers or staff reacting to news of a sale. Without those carve-outs, a buyer having second thoughts has a ready-made excuse.
What you as a seller should push back on: a definition broad enough to capture normal seasonal or cyclical trading swings, the absence of carve-outs for general economic and industry conditions, and no carve-out for effects caused by the announcement or pendency of the transaction itself.