Hours after Kate Upton used Twitter Thursday to accuse Guess co-founder Paul Marciano of using his power to “sexually and emotionally harass women,” the company’s shares dropped almost 18%.

Guess lost more than $250 million in market value in one day. Despite the company issuing a denial of Upton’s claims, shares continued to slide on Friday.

Upton’s allegations show that #metoo sexual misconduct claims can hurt company’s shares big time – even when those accused offer strenuous denials.

In the case of casino mogul Steve Wynn, the loss is in the billions.

The Wall Street Journal reported on Jan. 26 that Steve Wynn, the casino mogul and founder and CEO of Wynn Resorts, had been accused of sexual harassment and assault by several employees, including one allegation that lead to a $7.5 million settlement. In a statement to the Journal, Wynn denied the allegations.

A denial from Wynn didn’t stop the damage to his company. Shares for Wynn Resorts fell by 10% on the day that the Journal published its story and another 9% on Jan. 29, shaving off about $3.5 billion of the company’s value, according to Fortune. Wynn lost $412 million of his net worth.

Upton, who has modeled for the fashion brand, first made her claims against Marciano in a Twitter post on Thursday, writing: “It’s disappointing that such an iconic women’s brand @GUESS is still empowering Paul Marciano as their creative director #metoo.” She then posted a screenshot of her tweet on Instagram, adding the caption: “He shouldn’t be allowed to use his power in the industry to sexually and emotionally harass women #metoo.” Upton did not respond to TIME’s request for comment.

Marciano, who did not respond to TIME’s request for comment, denied the claims. He told TMZ that he didn’t know what Upton’s allegations were, and said that “if she has a claim, there’s one place to tell the truth and that’s in court or to the police.”

In an SEC filing on Thursday, the company said: “Mr. Marciano denies any misconduct toward Ms. Upton,” but said the company would investigate her allegations. It also said that it had investigated, with the help of outside counsel, claims from two other women, which were published on Jan. 31 on entertainment website The Blast. It said Marciano also denied those allegations and that the company was unable to substantiate the claims.

Billionaire Steve Wynn, chairman and chief executive officer of Wynn Resorts Ltd. Bloomberg - Bloomberg via Getty Images

Wynn, in responding to sexual misconduct claims in the Journal said in a statement: “The idea that I ever assaulted any woman is preposterous. We find ourselves in a world where people can make allegations, regardless of the truth, and a person is left with the choice of weathering insulting publicity or engaging in multi-year lawsuits. It is deplorable for anyone to find themselves in this situation.”

But some companies who have had prominent employees face allegations of sexual harassment haven’t seen their stock prices take a hit. Marketwatch noted that CBS, Netflix and Amazon’s stock prices remained steady after prominent employees were accused of sexual misconduct.

Sexual harassment allegations have cost companies in other ways beyond share prices. In May 2017, Fox News said it had paid $45 million related to litigation costs related to sexual harassment allegations. Netflix reportedly lost $39 million for cutting ties with Kevin Spacey, who was accused of sexual misconduct by several men. (Spacey apologized and said he didn’t remember the first allegation, made by actor Anthony Rapp, but hasn’t commented on subsequent allegations.)

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Write to Samantha Cooney at samantha.cooney@time.com.