The conventional wisdom is that MAE/MACs in merger agreements provide an opportunity for buyers to renegotiate merger agreements in the event of intervening adverse events. However, the experience following the COVID-19 outbreak suggests that the conventional wisdom is incorrect or at least overstated. In fact, MAE/MACs shift the risk of exogenous adverse events (like COVID-19) to buyers while leaving only the risks of adverse endogenous and semi-endogenous events with the seller. The consequence of this risk-shifting is to strictly limit the circumstances under which a buyer can credibly lean on a MAE/MAC to threaten to terminate a merger agreement and initiate a renegotiation. Parties to merger agreements appear to have internalized that lesson, as demonstrated by the relative paucity of renegotiations in the immediate aftermath of the COVID-19 outbreak.
Brian JM Quinn. "Mergers, MACs, and COVID-19." University of Richmond Law Review 55, no.Winter (2021): 565-613.