From Sidley Austin:

As the COVID-19 pandemic began to unfold in the US in early March, it quickly became clear that the crisis would act as a “poison pill” that would sharply reduce shareholder activism in the spring. Initially, many activists were preoccupied with their own survival and/ or attracting new capital rather than launching new campaigns. Additionally, it became difficult to obtain shareholder support for public activist campaigns at a time when boards and management teams were focused on managing through the immediate crisis. M&A activity, let alone hostile takeover activity, came to a halt.

In this environment, conditions were ripe for a surge in adoptions of literal poison pills, formally known as shareholder rights plans…In the first few weeks of the crisis, more than a dozen pills were adopted…Since the crisis began, approximately 70 companies adopted “poison pills” through the end of August. To further put this number in perspective, only 25 S&P 1500 companies had a poison pill in place at the end of 2019, according to FactSet.
…Many activists are building positions and are reaching out to the companies that are next on their current hit list. It is not necessarily the case that strong stock price performance protects you.