What is a MAC clause?
A Material Adverse Change (MAC) clause: sometimes called Material Adverse Effect (MAE): is a deal-protection provision in M&A agreements that allows the buyer, or a lender under a credit agreement, to terminate or refuse to close if a defined adverse event materially impacts the target between signing and closing. MAC clauses sit at the heart of deal certainty bargaining: sellers want narrow exclusions; buyers want flexibility to walk in a downturn.
Anatomy of a MAC clause
- General definition: any change, event, or circumstance that has or would reasonably be expected to have a material adverse effect on the business, results of operations, financial condition, or assets of the target.
- Carve-outs (exclusions): general economic conditions, market conditions, industry conditions, war/terrorism, pandemics (post-COVID), changes in law/GAAP, acts taken at buyer’s request, public disclosure of the transaction.
- Disproportionate impact qualifier: carve-outs typically apply only to the extent the target is not disproportionately impacted relative to industry peers.
Delaware case law: the high bar
Delaware Court of Chancery rarely upholds MAC claims. Key cases: Hexion v. Huntsman (2008, MAC not triggered despite severe earnings decline), IBP v. Tyson (2001, MAC requires durationally significant decline), Akorn v. Fresenius (2018: the first successful MAC finding, requiring 86% EBITDA decline plus FDA compliance failures). Standard formulation: a MAC must be “durationally significant”: measured in years not months, and materially affect the target’s earnings power.
The signing-to-closing gap and COVID-19
The gap a MAC clause polices can run from days to more than a year in deals requiring regulatory approvals, and the clause exists to allocate the risk of unforeseen deterioration across that period. The COVID-19 pandemic tested it directly and generated extensive MAC litigation. Courts generally found that pandemic-related impacts fell within the “general economic conditions” or “pandemic” carve-outs where those were present, preventing buyer terminations. In AB Stable v. MAPS Hotels, the exit that worked was a different one: the decision found that a Material Adverse Effect had occurred where the seller’s hotel operator made unauthorised changes to operations in response to COVID, breaching the ordinary-course covenant, a separate exit path that proved more enforceable than the MAC itself.
MAC vs. specific termination triggers
- MAC clause: general protection, hard to trigger.
- Specific conditions: bring-down representations, regulatory approvals, financing conditions, minimum financial metrics: easier to litigate.
Negotiating MAC in Turkish cross-border deals
For Turkish founders selling to international acquirers, MAC negotiation carries added weight given Turkey-specific volatility in currency, regulation and political risk. Sophisticated sellers press for narrow MAC definitions anchored to specific quantitative thresholds, for example a 20%+ revenue decline over multiple quarters, rather than an open-ended materiality test. They also seek broad carve-outs drafted for Turkey-specific risks, including currency devaluation, capital controls and changes in Turkish regulation, together with specific exclusions for known pre-signing concerns already disclosed in due diligence. The points worth settling in the same negotiation are carve-out scope, quantitative threshold design and the dispute mechanism that will decide whether a MAC has occurred.
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