The market may see more oil and natural gas companies adopt poison pill strategies as managers and boards attempt to protect their independence in an uncertain, volatile environment.

"When survival, or at least independence, is at stake, companies may trade short-term security and valuation against longer-term optimization," Rice University's Jones Graduate School of Business professor William Arnold wrote in an email. "I would expect to see more poison pill defenses to deal ... with both known knowns and unknown unknowns. The latter might include sovereign wealth funds."

"If [companies] have been doing their homework over time, they have probably identified potential acquirers, but in these unprecedented times there could also be unidentified stalkers," Arnold explained. "There are plenty of investors out there looking to make a strategic play at the 'right time.'"

The unprecedented developments include a likely recession and the fall of stock prices in many industries as the health and economic effects of the coronavirus pandemic spread across the world. Williams Cos. Inc. and Delek US Holdings Inc. each announced limited duration stockholder rights agreements to prevent any one group or person from acquiring a controlling interest in the company. This year through March 19, Williams' shares have declined 54.38%. Delek's have lost more than 65% of their value.

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Delek's move is a direct response to a potential hostile bid from activist investor Carl Icahn. Another target of his, Occidental Petroleum Corp., adopted its own shareholder rights plan after Icahn acquired 10% of the company's outstanding shares.

Williams' decision to swallow the poison pill may be more of a precautionary measure, said Miller/Howard Investments Inc. portfolio manager John Cusick and Hunton Andrews Kurth LLP partner Michael O'Leary. Once an entity acquires 5% or more of Williams common stock, that company's agreement enables a rights holder to buy a number of Williams shares with a market value of twice the exercise price.

"There doesn't appear to be anyone who has recently filed an [SEC] Form 13D indicating they own 5% or more, so I think they're just doing it … to not have some person come in and take advantage of the particularly low price and buy up a substantial block and then put pressure on the company to try to do something in this environment," O'Leary said in an interview.

For Cusick, the Williams poison pill may be an effort to avoid another failed M&A transaction. "I wonder ... if it's proactive because of what they went through with Energy Transfer LP a few years ago," he said in an interview.

Cusick was referring to an event in 2016 when what was then Energy Transfer Equity LP walked away from acquiring Williams after several months of negotiations. ETE's enthusiasm turned into buyer's remorse when its law firm could not generate a tax-free opinion for the combination.

Hunton Andrews Kurth's O'Leary said he expects to see more midstream poison pills, even though institutional investors generally do not like them.

"The limited duration approach [of the Williams arrangement] … is I think an attempt to address some of their concerns," O'Leary said. "Under the circumstances … I think institutional investors understand in this environment it does make some sense."