This post has been updated with Bloomberg announcing Friday he’ll allow three women to be released from their confidentiality agreements over legal disputes about comments they allege he made to them.

When Sen. Elizabeth Warren (Mass.) went after Mike Bloomberg at Wednesday’s Democratic presidential debate for nondisclosure agreements he has with women he worked with, she missed some important context about how the legally binding agreements are used in the business community, say two legal experts: mainly that they are extremely common for workers in the private sector to sign and a common tactic after all legal disputes. Plus, they can be beneficial to the person alleging sexual misconduct.

That’s not to say that Bloomberg, a billionaire businessman and former New York mayor, is in the clear on allegations that he verbally harassed women who worked at his company. He settled with an unknown number of women, and the details of those cases remain private because of the NDAs both sides signed.

Under intense pressure from Warren and former vice president Joe Biden on Wednesday, Bloomberg refused to say he would lift those restrictions, brushing aside the allegations of his verbal harassment as: “Maybe they didn’t like a joke I told.”

On Friday, he suddenly changed his mind and said he’ll allow three women who he said have NDAs with him over gender-related disputes to ask the company to be released.

Before we possibly learn more about what these women alleged, let’s review some context about NDAs.

An NDA is exactly what it sounds like, a legally binding agreement not to talk about certain things. “It’s essentially a confidentiality agreement,” said Jeffrey Jacobovitz, a white-collar defense lawyer. If someone breaks an NDA, they can technically be sued, but Jacobovitz said that doesn’t happen often in the public sphere because it could look overly aggressive.

They were traditionally used for specialty cases, such as celebrity nannies or personal assistants. But over the past decade, NDAs have also become common for workers in the private and nonprofit sector to sign upon being hired, said Melanie Sloan, an ethics expert. “It’s not nefarious,” she said. “It’s to prevent people from talking about what the business was doing. You don’t want to give trade secrets to your competitor.” Pete Buttigieg, a former mayor of South Bend, Ind., and a Democratic presidential candidate, signed one when he was a business consultant to prevent him from talking about how he was advising other companies.

NDAs are relatively new to politics. The Trump White House is the first to bring the practice in widespread form from the private sector, making top aides sign them. They were very rarely used in the Obama White House, as Ian Bassin, a former White House counsel, said in 2018.

When NDAs are used in sexual harassment or gender-discrimination cases, they can certainly be used to silence women about the alleged crimes they encountered, as Warren and Biden alleged with Bloomberg.

“You think that women, in fact, were ready to say, ‘I don’t want anybody to know about what you did to me?’ ” Biden said. “That’s not how it works.”

But they can also be used to protect those women, Sloan said. Fair or not, if you need to get another job, being out there accusing your former employer of sexual harassment isn’t always the best look.

As The Washington Post’s Michael Kranish has reported, it’s not clear that one of Bloomberg’s most high-profile accusers, former Bloomberg saleswoman Sekiko Sakai Garrison, wants to talk. “She has not responded to requests for comment,” Kranish wrote. She reached a settlement years ago “in the six figures” after alleging that Bloomberg twice told her to “kill it” when he found out she was pregnant.

NDAs aren’t always easy to get out of. “It’s easy,” Biden said to Bloomberg on Wednesday. “All the mayor has to do is say, ‘You are released from the nondisclosure.’ ”

When Buttigieg was getting pressure from his opponents to share what clients he advised as a consultant, he asked his company, McKinsey, to release him from the NDA. They eventually obliged, calling it a “unique circumstance.”

Saying a few words to end an NDA could be the case if Bloomberg was the defendant in these cases. But Jacobovitz said that often in sexual harassment cases leveled against someone in the company, the lawsuit is directed at the company, and thus the company controls the parameters of the NDA. You might need the company’s lawyer or board to intervene to end an NDA.

Of course, Bloomberg is the chief executive of his financial services and news company, so his words carry a lot of power. And that’s why he seemed to be able Friday to reverse the NDAs with a tweet.