Cyber risk is something to think about every day, and management teams must be willing to get in front of the issue, said The Walt Disney Co.’s finance chief.

“It is not a risk that is kind of ‘check the box.’ It’s a risk that you have to think about daily,” said Christine McCarthy, Disney’s senior executive vice president and chief financial officer, speaking last week at the Professional Liability Underwriting Society’s 2019 Directors & Officers Symposium in New York.

Ms. McCarthy said it is important to establish protocols “around things that could go wrong” and invest in technology and new systems. “It doesn’t come free,” said Ms. McCarthy. “Cybersecurity is something we think about all the time.”

Meanwhile, during a session on cryptocurrency, including initial coin offerings, David Murray, financial lines head of product innovation for American International Group Inc. in New York, said AIG, like most insurers in financial lines, is taking a cautious approach.

“Our appetite for this risk continues to be limited, and largely that’s a reflection of regulatory uncertainty,” which is the biggest challenge, he said.

But there are other challenges as well, he said, one of which is that many of the companies in this area are at a “very early stage” with an idea for blockchain technology but no financial statements and “really no experienced management team.”

Even the technology folks, he said, “are relatively new to the space,” so even if blockchain and cryptocurrency were taken out of the mix from a D&O perspective, “that is a high risk” with a “high degree of failure in the near term,” said Mr. Murray.

“There is a problem just with understanding the technology and understanding the risk it represents,” he said.

A third challenge is that “we really don’t have any kind of claims history or loss history in this space because it’s brand new,” Mr. Murray said. While there have only been about a dozen securities class actions in the space to date, “there may be many more cases in the pipeline,” he said.

The growing number of securities class actions and derivative litigation was discussed during another session. According to data presented at the conference by Cornerstone Research and the Stanford Law School Securities Class Action Clearinghouse, for instance, 8.4% of U.S. exchange-listed companies were subject to litigation filed in federal courts in 2018, compared with 3.7% in 2004.

Susan S. Muck, a San Francisco-based partner with Fenwick & West LLP, said, “I think at this point you’re primarily seeing different law firms getting involved on the plaintiff side, and I would characterize this set of firms as less discerning, bringing back a bit of the race to the courthouse.”

“For a long time, we saw cases filed weeks or months after a stock price declined,” she said. Now, “cases are filed almost immediately after a stock price decline.”

During a session on D&O-related U.S. Supreme Court rulings, a panel discussed the court’s March 2018 unanimous ruling in Cyan Inc. et al. v. Beaver County Employee Retirement Fund, which held that class actions related to initial public offerings can be heard in state court.

The ruling’s practical effect is there will still be litigation in federal courts, “but then other plaintiffs will file in state courts,” said Douglas W. Greene, a partner with Baker & Hostetler LLP in Seattle.

During another session, there was discussion about directors and officers often being named as defendants in lawsuits filed by retirement plan participants who are charging their companies’ 401(k) plans have unnecessary and undisclosed fees.

Rhonda Prussack, New York-based senior vice president and head of fiduciary and employment practices liability for Berkshire Hathaway Specialty Insurance Co., said those who serve on their companies’ compensation committees are defendants in these suits, and it is “very common for the members of boards of directors to (also) be named in these suits as the parties who selected the members” of these committees.